I like Hat, Caesar and Zvezda minis. Have some marching on my desk at work I'll try to send some photos later. Hat 1/72 plastics are very cheap and available from a variety of eras, Roman, biblical, up through middle ages etc. Zvezda doesn't have as big of a line for historical minis but the quality on what they have is SUPER detailed.
Plastic Soldier Review
Current HaT Production - Ancients
Plastic Soldier Review is a great place to see what is available and get highly detailed reviews of the products. You can also learn some history there reading the reviews.