Dollar General, Walmart, K-Mart and etcetera, but only if the photo is in a standard size. If it is in an odd size and it requires custom framing, it's going to be quite a lot more expensive. You can also go to an artist's supply shop and get precut mats, but again, this only works if the print was made for a standard sized mat. Otherwise, you have to cut your own or get someone to cut them for you. If you are going to be doing this a lot (or come to think of it, more than a dozen times), get an inexpensive Logan mat cutter and learn to use it. You will find it is a VERY worthwhile investment. If your print is in a strange size, then probably your best bet is going to be to go to a store that sells some-assembly-required frames, like Michaels. There you can choose two sides and a top and bottom and put them together yourself. You will still have to get a piece of glass cut.
Oh, about what Photomark said. He must have been doing his own framing for a while now, or things are very different in Australia, because the cost of custom framing has gone through the roof here in the USA. Professional framing isn't a "bit" more expensive anymore. It is very expensive to have a professional in a custom framing shop do all this for you. $50 or more per print is not unusual.
I was under the impression that this was for a show, where there is some glory but no money involved. How much are you considering asking for your prints? If you are selling your prints the price of framing and matting shouldn't be a consideration -- unless you are seriously undervaluing your work. I woulden't even consider letting one of mine go for less than $1000 and that is for one of the smaller and less important ones.
Well, considering im still newer to the photography world. That's why I wanna get ahold of cheap frames. Because, my work isn't $1000 worthy. At 8X10 I'll be lucky to make like $50. But the only reason why I'm selling some prints is to help with getting new/better gear. I mean, my 50mm was pretty cheap, but the next one im looking at. It's like a $600 lens new. So, I figure, mine as well try. See if they sell. If they don't. I'll give them to family members as gifts. If they do, it's a little extra money towards my next lens. I wish they were show worthy, but I have a long ways to go before I'm at that level.
you will not get pro framing and mounting for that but I do get 8 x 10 photo frames from the $2 shop ( bargain variety type store) for a few dollars. Also most supermarkets also sell cheap photo frames
$15 will get you a very nice frame with professional framing costing a bit more