Cheap way to check pH of course is testing strips..
Cheapest way to adjust pH is vinegar/lemon juice to lower pH..
Backing soda will raise it..
Adding lime to your soil will keep soil from going too high, will keep it @ or under 7
good luck
PS I dont mind helping out a new user, and dont take this the wrong way..
BUT check the FAQ, ALOT of this basic type of stuff is already talked about..
ALSO the 101 already asked questions sticky
GROWFAQ