Diana Ross, the Supremes, Etc., Etc. …

Yes, summer — known to music lovers as the season of the monster tour — is here. (Well, all right, technically it’s not here ’til about the 21st, but whatever.) For our purposes, summer is on. But with the number of stadium tours — Britney Spears, ‘N Sync, Metallica, Dr. Dre, Santana, etc. — gearing up for the road in the coming months, chances are some acts will be squeezed out at the box office.

Case in point: Diane Ross and the Supremes. The legendary Motown trio kicks off its 30-date, two-and-a-half-month-long tour tonight in Philadelphia. And looks like neither the pre-launch hype (doing Oprah) nor the controversy (doing it without the original members) has helped. Response for the tour has been lackluster, and what’s more, there’s no sign that sales will pick up.

Is Miss Ross the victim of an oversaturated market? Perhaps.

“There’re a lot of different acts touring this season,” says Gary Bongiovanni, editor of the tour industry mag Pollstar. “Summer concert business is very busy. And there’s probably more business than the market can handle.”

With that thought in mind, here’s a look at some of the acts that’ll be competing for your paycheck (or allowance) this summer.

Reunions and Comebacks (aka Old Farts)

“The Supremes — Return to Love”: A reunion tour (of a sort), with only one of the group’s three original members (hello!), Diana Ross, on the bill. Besides the hammy presence of Miss Ross, expect rehashing of golden Supremes oldies and excessive costume changes on a tour that’s slated to end Aug. 5 in Vegas. The Who

“The Who — Greatest Hits Tour”: Everyone else has done it, so why not the Who? Brace thyself: The old guards (literally) of British rock are brushing up their dentures for a 20-date tour that’ll kick off at the World Theater in Chicago on June 25. Unlike their previous outings, the lineup this time around is decidedly small. In addition to original members Pete Townshend (guitarist), John Entwistle (bassist) and Roger Daltrey (vocalist), the five-piece band will also include new guys Zak (son of Ringo) Starkey (drums) and John Bundrich (keyboards).

Bob Dylan: Fans who missed Dylan’s brief tour earlier this year may breathe a sigh of relief. The reclusive music legend is coming back out for a 32-date U.S. tour that’ll start in Portland, Ore., on Friday. Repeat viewings are recommended. It’s been said that Dylan doesn’t play the same song list every night.

Santana: Now we don’t know if all those musicians Santana collaborated with on “Supernatural” are going to be there, but the multiple Grammy winner is definitely going to hit the concert trail. His summer tour, covering the United States and Canada, will begin July 20 in Florida and will end Oct. 26 in Vancouver, B.C.. Teen Spirit and Barely Legal (aka Future Has-Beens)

Ricky Martin

Ricky Martin: This guy’s still living la vida loca. (Yes, we’re so clever!). Pop king Martin has plunged straight into the second leg of his world tour after finishing a series of sold-out dates in Europe. The pelvic gyrations and bon-bon shaking began June 9 in Fort Lauderdale, Fla., and will finish July 27 in Portland, Ore.

Britney Spears: Perhaps it’s the “rake-‘em-in-while-you’re-hot” mentality, but 18-year-old Britney Spears seems to have no intention to ever stop touring. On the road since March, the popstress will come back from a two-month hiatus to resume her North American dates on Thursday in Charlotte, N.C. After the tour wraps (on Sept. 5), word has it that the teen princess has her eyes set on Europe for her next round of assault.

Christina Aguilera: Couldn’t get Britney tickets? No worries, just go see Christina Aguilera. The millennium’s new Tiffany has finally got what every teenybopper wants -– her very own headlining tour. With Destiny’s Child in the opening slot, the tour opens July 31 in Milwaukee and ends Sept. 25 in Florida.

‘N Sync: It doesn’t take a genius to guess that ‘N Sync, the boybanders who sold 2.4 million copies of their sophomore album “No Strings Attached” in one week, can also sell out entire stadiums. The group’s current full-length U.S. tour started in May. It’s scheduled to end July 30 in Hershey, Pa., — let the scalping begin. Mosh Pit and O.G. (aka The 16-24 Male Demographic)

Dr. Dre

“Up in Smoke” tour: This much-anticipated rap package brings together some of the most respected old-school and new-school gangsta acts (including Dr. Dre, Ice Cube, Snoop Dog, Eminem and Warren G.), not to mention some of the baggiest pants you’ve ever seen. The 25-date tour begins Thursday in Chula Vista, Calif., and will wrap in Florida on Aug. 2.

Pearl Jam: Seattle’s second best-known grunge band sets out to prove that — after all these angst-ridden years — they can still push T-shirts and bumper stickers on the kids. Playing in support of their sixth album, “Binaural,” Pearl Jam will inaugurate an extended 40-date U.S. tour in Virginia on Aug. 3. The tour is tentatively scheduled to end in the boys’ home city Nov. 5.

“The Summer Sanitarium Tour”: Aren’t those boys cute when they’re angry! Noisy boybands Metallica, Korn, Kid Rock, System of a Down and Powerman 5000 headline the festival tour that’s sure to awaken the nihilistic impulses of sheltered suburban kids. The mayhem kicks off June 30 in Foxboro, Mass., and will end July 16 in Queen Creek, Ariz. Other Country Elements (aka A Sans Garth Brooks Summer)

The Dixie Chicks

“Fly Tour 2000”: Apparently, Christina Aguilera is not the only virgin here. This summer, the Dixie Chicks have also decided to set out on their first headlining tour. The trio’s five-month itinerary kicked off June 1 in Canada. “Soul2Soul Tour”: The two souls in question are none other than Mrs. Tim McGraw and Mr. Faith Hill — or as they’re more popularly known, Faith Hill and Tim McGraw. The country power couple jointly hits the road on a 23-date tour beginning July 12 in Atlanta.