Really, bows are fairly expensive bits of kit, and it's just about the same as with everything else in my experience - you get what you pay for!
I assume the age in your profile is accurate? I'm not really sure what you'd get out of a cheap bow. When I was about 7 years old I got my first bow, a fibreglass one for about £20 and a draw weight of about 15-20lbs IIRC. It was SO much fun, I had a blast with that bow and quite literally, if I wasn't in school, I would be running around on the beach, up hills and down rivers with that very bow. I still have it, lots of sentimental value (and a string that's probably full of more germs than your average hospital
) but it's no longer satisfying to shoot, except playing around. 40-50lbs suits better, now.
I would be very surprised if this bow had a greater draw weight, but if it says you may as well post it here, as it is an important factor.
The draw weight is the amount of force required, in pounds, to pull the string back to a certain draw length - usually 28". Basically, this means that if you hold a 30lb bow horizontally by the handle and hang weights on it, the string will be 28" from the handle when you put 30lbs worth of weight on the string. In other words, when you draw the string back to 28", two or three fingers will be holding 30lbs of weight. This, therefore, must depend very much on your physical ability. When I was shooting my little bow as a kid, I could shoot my best friend's mom's 30lb bow - but it was uncomfortable, I couldn't keep it up for long. In this sense, your average grown man may suit a 30lb bow to start, give or take 5lbs and work up to maybe 50 or 60 depending on their needs and what they want to use it for. Some people shoot bows upwards of 100lbs, though I can't fathom why myself, unless you're shooting at something the size of an army quite a distance away!
Also take draw length into account - this is the distance you will pull the string from the handle of the bow. For me that's about 32". Fibreglass bows are much more forgiving than wood bows for this, I think, but you can break a bow by pulling the string back too far so take it into account. I've seen numerous bows recently that had neither draw weight nor length advertised and it drives me nuts
The old rule of thumb is that you should pull the string back far enough to touch your chin and the tip of your nose (while I pull it back that far in practice, I don't let it touch my face, I have a lip piercing and that could go bad quick!)
I hope that answers a few questions. Ultimately, much will be learned from more knowledgable bow shooters, and from experience, but I hope that's helped a bit anyway. A nearby school would be a great start.
Pete
I was thrilled, it was by a small scottish business as well. Strung it up, drew it back and bam, string shot halfway down the length of the arm, which quickly became "the arms" 
Shredded the string pretty good and scared the bejesus outta me! Upon inspection it looked like the fibreglass had worn away, allowing the string to catch on the wood and split it open.
Or is that just because I'm getting lazy in my old age.
