Most shoes will fit a number of different pedal systems. Any shoe that will work with a LOOK cleat will work with Speedplay.

Speedplay is a pedal system. You buy the pedals and they come with the cleats that you attach to your shoes (which you'll have to buy separately). Once the cleat is installed on the shoe you can clip into and out of the pedals. LOOK is pretty standard and almost all road shoes are LOOK compatible. Shimano SPD-SL, LOOK (and all the knock-off brands based on LOOK pedals), LOOK KEO, Speedplay, and Time pedal systems all work with the three bolt pattern in 99% of all road shoes.