Can't see any pictures yet, so it's a bit hard to say much about it. False Cypress seem a bit unusual as a species for a beginner, but that doesn't mean it wouldn't be worth a shot if you found something that interests you in the tree. Just make sure you get help from someone experienced or it will not be a very good learning experience for yourself. I know I saw a pretty cool example of this species on here not too long ago, hopefully they will chime in. I have this bookmarked from about a year ago, so don't shoot me for sending you to another site...one of the members here wrote this nursery stock tutorial so check it out if you haven't:
http://www.bonsaisite.com/forums/index.php?showtopic=9905
To sum it up, go look at as many plants as you possibly can. Look for something that will lend itself to bonsai. Check the trunk, taper, base, roots, and movement. You have to remember that if it doesn't have at least 2 of those things, it's going to be a long slow ungratifying road for the next few years and quite possibly will never have much potential. What I seem to notice is that people either look at only the biggest stock or they buy a stick. Don't exclude the shrubs, they often can be easy to work with. My suggestion to you is to pick something that will backbud easily and grow fairly quickly. Having those two qualities will allow the plant to overcome any mistakes you will inevitably make as a beginner. From one beginner to another, I can tell you that you can almost butcher a barberry, cotoneaster, boxwood, or crape myrtle and they wont skip a beat. I won't give much advice outside of those species because I've not had any experience. Another reason these deciduous species are great for a beginner is because when you make drastic cuts in spring you get enough growth throughout the year to feel like you have made some progress. One of your biggest issues as a beginner will be wanting some sort of success to keep you interested; patience is not something we are born with.
As far as the price tag, you are on your own. Unless I really really liked a plant and it had some fantastic features that translated well to bonsai, I would not spend $50. You have to remember that these plants will usually be years behind developed stock. On the other hand, your budget is no doubtedly different than mine. Other people on this website wouldn't think twice about buying $50 material in droves for future projects. It is all relative to the buyer.