Hi Ektagraphic,
Having someone say "I love your work and I want it on my wall - here's some money" is just the best feeling. I had the pleasure of selling three large prints in one night for £75 (abt. $100 US) each at my final year exhibition at Uni. I was told it was a very reasonable price in 2007; if I had the opportunity to sell work today I'd certainly charge £100+ (abt. $150) for the same prints.
My tip - be a real sniffy perfectionist. Make sure your prints are properly developed, fixed, archivally washed and pristine, with no visible dust marks, blotches or other defects. The last thing you want is your print that you charged $100 for discolouring on someone's wall in five years. You may think 'Oh nobody will notice that little spot in the corner', but if you can see it, someone else will. Make sure the matting and framing are straight and perfect, no dust or fingermarks inside the glass. Use a simple, tasteful frame. Signing and numbering the print is your choice - I do sign and number my prints. Who knows, you might be collectible one day.
Then, as the others have said, price your prints reasonably but not cheaply. Make sure people know what they're getting for their money, and why they should pay more for Ilfochromes than inkjets. What if someone asks "His prints are far cheaper than yours - why?".
Be proud of your work, and I wish you well with it.