Recently a guide on how to buy your first guitar was posted and I have just a few extra suggestions on what exactly you ought to do.
1. Find out what feels comfortable.
It seems rather obvious, but you might be surprised how many people pass this one by and, instead, pick up the coolest looking guitar only to have a clunker that plays like a beached whale.
When looking for comfort, think about weight (is it really heavy? Les Pauls are likely the heaviest guitars you'll find, compare!) size (I play a semi-hollow and it is really big for me, you may want to consider a little shredder model like an Ibanez or a Fender which is more compact) and features (which is really just a decision on your tremolo system (or lack there of); hard tails (guitars without whammy bars) are generally easier to tune and require less work to stay in tune, but lack the fun that can be had WITH the tremolo).
2. Find out what is on sale.
Often times you'll think you've found the best guitar possible and then your eyes will hit the price tag. Not to fret! You can usually find models which are similar to the one you want, but since they are (used/damaged/display models) they are often quite a bit cheaper. Don't count out a first guitar just because the paint is a little chipped! If you stop playing you can hang it on your wall and say it was your old touring instrument.
3. Find out what inspires you.
It is no small coincidence that there are tons of guitars in your local guitar shop that will be in a beginners price range ($300-$500). Companies want you to buy their guitars. Don't be ashamed to go for cool if you think you'll like it.
Don't go for cool and be ignorant of everything else that was noted above, because spending $400 for a guitar that is uncomfortable and sounds bad is a sad way to be out of $400.
4. Most of all, compare!
If you think you like a guitar and your heart is set on it, humor yourself and try another one. Worst case scenario? You find you like the other guitar better, and now you know WHY you like it better.
I hope this illuminates what perspective guitar buyers should look for.
If you have any questions, send 'em to me @firstname.lastname@example.org