Here I'll jump in on this thread. I didn't quite make my outfit for as cheap as everyone else did but a lot of what I bought I can wear with regular clothes so I figured that justified it...
Hat is the "super" Indy hat which was about $100
Shirt is from H&M for about $30
Pants from H&M for $30
Belt is maybe $20, it's a leather belt and not a web like the real one, I may change that later.
Holster and whip holder was like $25 from ebay. It had a belt to but it was ugly and stiff and I decided not to use it. I actually got another black holster that looks pretty worn from an army surplus store, might use that in the future.
The bag was $25 from ebay. The leather strap I took off a bag I got at the rennfest so it took about $2 in hardware to attach it to that bag.
The whip is the Indiana Jones Halloween whip for like $7 off ebay. I will be getting the noble collection whip when it comes out.
The shoes which you can't see are brown Doc Martens which cost like $100 I think. But I had been wanting a nice pair of Docs so I can wear them with other clothes.