Generally the seller will pay the commission for a buyers agent (it is split between the two agents) BUT sometimes the seller does not pay commissions and the buyer will have to pay their agent the commission...this is rare. As Rob mentioned, you should clarify who will be paying the commissions at the start of the transaction as it is negotiable.
As far as getting a lawyer is concerned, if there is something in the contract you do not understand, it is advisable to get a lawyer. You can learn a lot on Google though :-)
Dec 16, 2011