I like ITC Serif Gothic. BTW Show us samples of what you're talking about …

Have you tried doing keyword searches on MyFonts?

disco:
http://www.myfonts.com/search?search%5Btext%5D=disco

70s, disco:
http://www.myfonts.com/search?search%5Btext%5D=70s%2C+disco

yep, i love serif gothic as well poms

if you're after a 'freebie', then alba is one of my recent 'finds'

If you are willing to wait for a few months then SteadyRockin might be your best bet...
Funky, loopy, swirly and OpenType all in one package...CAN YOU DIG IT...Cause I Can!

http://type.akofa.com/steadyrockin/index.html

From the friendly folks at AKOFAType where the impossible is only the unthought of...

Hey DJ, take a gander at: http://www.fontbros.com/cgi-bin/commerce.cgi?search=action&keywords=groo...

Almost forgot: http://www.fontbros.com/cgi-bin/commerce.cgi?preadd=action&key=ASOE-DIDO

Best,
Stuart :D