First off if you don't want something as big as a Sulcatta, then do not get a leopard. Leopards are very large tortoises as well, and there are records of some being as large as some Sulcattas. Leopard tortoises are the second largest African mainland tortoise next to the Sulcatta. Leopards are gorgeous tortoises but unless you have the room....move on.
Red-foots are pretty much America's number one pet tortoise. They are outgoing, attractive and easy to care for. However, the do once again attain a relatively large size. There are males being sold on the internet that are 14 inches or more. Red-foots also require a warm, humid habitat and do not hibernate. Basically if you want a leopard or red-foot make sure you have the room indoors and out because if you experience cold winters in your area the tortoise will need to come inside durring those months. Red-foots are highly adaptable to many areas but like I said they are a decent sized tortoise.
Russian tortoises are by far the easiest out of the species you mentioned. They are easily attainable, very personable and are extremely hardy. Unfortunately most being sold are wild caught adults and they are heavily infested with internal parasites such as nematodes. While these still can and do make great pets, you will have the added expense and time to get the tortoise treated and freed of parasites. Captive bred russian tortoises are now available quite often and even though they go for more than an adult (adults typically $40-$75, babies typically $100 to $150) they are totally worth it. Russians tend to stay fairly small with females reaching 8 inches ocassionaly, and males barely ever exceeding 5.5inches. Russians also hibernate, so if you cannot afford to keep your tortoise indoors durring the winter because of money, time, or space you can simply hibernate it from October until March/April by following one of the many "Safer hibernation for Tortoises" articles available through the internet or in books.
While Russians are very practical, I recommend the perfect tortoise being a Hermanns Tortoise. These tortoises are again a fairly small tortoise, are absolutley beautiful and are hardier than ever. They hibernate if need be with little or no problems, and adapt to any situation (providing the animal is kept healthy). These tortoises are also extremely personable and respond well to humans. Mine come running to me for food everytime I enter their area. Baby hermanns are also very easy to come by and breeders seem to always have them for sale at affordable prices ($100 to $150). There are two subspecies of hermanns tortoise and the one you would be purchasing is the eastern form, Testudo hermanni boetgerri. The eastern hermanns tortoise is a wonderful animal and perfect for any beginner.
Below is a photo of 2 of my Western Hermanns Tortoise, these are very rare but the appearance is very similar to that of the eastern hermanns.
Hope this all helps!
-Chris
