Orb weaving spiders are large (up to 1/2 inch long), brown, and have a round body. They are most easily identified by their large size and their round body.
The best way to get rid of orb weaving spiders is to eliminate their food sources by thoroughly cleaning your kitchen and bathroom. You can also use commercial fly traps or bait. If you have a severe infestation, you may need to call a professional exterminator.