Wifi Design Question

I'm tinkering around with an idea that would require controlling some hardware over a WLAN. I've got lots of electronics experience, but ZERO wireless experience. Are their single chip (i.e. CHEAP) solutions on the market that can plug into a design that handle the wireless junk for me? A serial or parallel output doesn't matter, I just want to be able to read and write data to some hardware using my wireless network.

Thanks for your ideas!