Hook Ups

TMZ has obtained a photo of the two of them at the Blue Nile jazz bar in New Orleans -- and one spy inside the joint tells us they were getting very hot and heavy with each other.

But before 50 got cozy with Chelsea, dude knocked out a live freestyle set with a local band at the club.

Check out the verse 50 busted out that night ... it seems to
be directed toward a special lady friend.

Downgrade.

The chick playing tonsil hockey with The Biebs is 16-year-old Jasmine Villegas -- who also happens to be the opening act on Bieber's concert tour.

The photos were taken on Thursday, September 9 in Venice, CA by some Canadian tourist who just happened to notice his country's most famous pop star in the midst of a make-out session with the luckiest teenage girl on the planet.

The two had been rumored to be dating ... but they insisted they were just "really cool friends."

Back in 2001, Kat Von D -- a famous celebrity tattoo artist -- was asked to ink a permanent image of Sandra's face onto the chest of one of her male clients who happened to be a huge fan of "Speed."

So there you have it -- Kat Von D is now dating the ex-husband of a person she once tattooed on a total stranger.

How's that for full circle?

Meanwhile on the same day, Kate's ex-husband Jon Gosselin played daddy day care with his eight kids and girlfriend Ellen Ross in Pennsylvania.

Aniston -- who will be guest starring on "Cougar Town" this season -- was photographed riding shotgun in Hopkins' ride after a romantic chow-fest at Madeo in Hollywood.

After being photographed on a dinner date in Vegas earlier this month, the tatted up couple were spotted walking hand-in-hand in Texas this weekend.

We're told Phelps took a bunch of photos and signed autographs for fans ... in between gettin' real close and personal with Miss Cali.

The friend -- someone we know spoke to Rachel yesterday -- tells TMZ Rachel said ... "I feel horrible for him. He loved her. But he was in love with me. I hope he remembers that was real, and reaches out to me."

Rachel added, "I'd give up everything to be with him again."

The pair had dinner together at N9NE steakhouse in The Palms ... during a weekend where they were seen acting "very affectionate" toward each other at several Vegas hot spots.

Jesse looks pretty intense in this photo -- but then again, dude takes food pretty damn seriously.

Ochocinco has been dating Evelyn Lozada (of VH1's "Basketball Wives") for the past several months ... and he has made no secret of their relationship (just check his Twitter once in a while). Things are so serious between the two, we're told Chad will be popping up on her show next season.

But sources close to the couple tell TMZ ... VH1 is pissed at Ochocinco about the relationship -- since he's the star of a dating show that's currently airing on VH1! We're told the network doesn't like the "spoiler" that Ochocinco doesn't end up with anyone on the show.