Look up the Fashion section of AskMen.com for some good advice on slick clothes.
Start out with the underwear and we'll go from there.
1. A&F Trunk Briefs (heather gray is best) or Boxers
2. Jockey white ankle socks / black dress socks
3. Straight-cut Gap blue jeans (dark stone wash) / Black dress slacks
4. U2 concert T shirt (they're all cool) / White 100% cotton dress shirt
5. Brown leather AE belt / black dress belt
6. Mock black combat boots / Black leather dress wing tips
7. Citizen Chronograph watch / Skagen mesh band
8. Gap military-style jacket / Black combed wool overcoat
9. Trendy haircut like Brad Pitt or Matt Damon
10. iPod Classic... loaded with ultra-cool songs by Moby, The Commodores, or John Legend.
Actual stores to recommend? The Abercrombie look is cool, to an extent. They go overboard with the slashed jeans and way-too-worn-out caps. AE tries to copy them too much. Gap is just about perfect when it comes to balance like that. Also, for dress, Hugo Boss.
Damn I'm good at this