Here ya go.Basically, once cycled, your Ammonia and nitrite levels should be zero, and your nitrates should be under 40ppm, otherwise time for a water change. pH should be near around 7.
I'm new to this, but I've read that most aquarium enthusiasts prefer the liquid testing kits to the strips for accuracy.
I bought
this one which seems to be the standard. It's a few bucks more than the strips, but it should last you for as long as you need it. Once your tank is established, you shouldn't need to test your water all the time... only when you suspect problems.
Also, many local pet and aquarium stores will test your water for free. I know Petsmart does.