Dog that has epilepsy. Not sure what to do.?

we rescued a pit/lab mix in Tucson 1 year and 2 months ago. He had no indication of any health problems but on March 10th of 2011 he had a seizure which has never happened before while with us then he had 2 seizures within a 7 hour period on March 15th we took him to a vet and spent 700 dollars trying to figure out what is wrong with him. The vet said he is perfectly healthy they did blood test and such. We then ordered medication online because we didn't want to use harmful chemicals in his body and we wanted to go the natural way we then started giving him the meds then he had another seizure on March 30th and then his last seizure was April 10th. We are going to take him to a homeopathic vet who has Chinese medicine I am not sure what to do because we are college students and we don't have a lot of money. I love my do to death he means a lot to me. He is extremely sweet. I worry all the time that he is going to have a seizure when I am not home. This worries me even more because we have a year old lab and they are best friends but I have read the dogs who have seizures can sometimes attack. Any suggestions?