Check your local newspaper's classifieds, especially on Sundays, for studio monitors. Because the technology is evolving so rapidly, people who record buy new equipment often--not because their current equipment is faulty, but because they want newer stuff. You might be able to find quality monitors and take someone's old monitors off their hands for a bargain of a price.
Log onto musiciansfriend.com and type "studio monitors" into the website's search bar in the upper-left hand corner of the window. Musician's Friend is known for selling new music equipment at bottom-of-the-barrel prices. They offer used equipment even cheaper. Subscribe to the free catalog at their website for up-to-date deals.
Search secondhand sites like eBay and music123.com/outlet for slightly used, but much cheaper equipment. Watch items on eBay and wait for a few days before you make your purchase, since new deals are constantly going in and out of the site. Try to refrain from buying the first monitor you see.
Call recording studios around your city or the nearest college town/big city. Many have loads of equipment they seldom or rarely use. Tell them that you're looking for studio monitors and see if they have any they can sell you. If they don't, they might know someone who does, since they frequently deal with people interested in recording.
Stop by your local pawnshops. One of the great things about pawnshops is that they buy as well as sell. Bring in your old guitar, DVD player or anything else you want to get rid of and trade it toward the purchase of your studio monitors. Many times pawnshops will pay you more in store credit than they would for cash, which means you can get the monitors even cheaper.