Well you have alot of options when it comes to buying your first unicycle. Its kind of tough at first especially when you really start looking around. There are several manufacturers across the globe.
I just recently started about a month ago and made an impulse purchase at my local bike and hobby store. Every time I drove by I saw their unicycles in the window. Finally on my birthday I marched down there and picked one off the wall. I have a torker cx 24 inch. it cost me about 120 dollars.
Now, since Ive looked around on the internet I’ve found that I really spent way too much for it. You can look on ebay and find some great deals on the same one I have. From reading on the forums I’ve found that alot of people bought the same one I did for their first uni and later moved onto something better after they had learned how to ride it. Also unicycle.com has an excellent selection.
Just remember there are alot of crappy uni’s out there as well as some very expensive ones. I would start off small and work your way up. Luckily I made a good purchase without knowing it.
Theres some great tutorials you can find on this site if you look around. One of the best ones I’ve read is dudewithasock’s beginning journal, I found it helped quite a bit just reading someone going through the same frustrations and conquering them with determination. Ill put the link for it at the bottom.
If you imagine balancing a straight object upright on the palm of your hand, like a tennis racket, or a baseball bat. This is very similar to keeping a unicycle upright. if the top starts moving forward you have to move the bottom forward. and vice versa for all directions. It helped me understand what was going on.
Remember when you do get your uni and start to ride it. you will fall down. so keep safety gear in mind. WEAR A HELMET.
Here is the journal I was talking about.
Good luck! and make sure you STAY SEATED.