I wouldn't buy from a ticket brocker myself, but I just read a good article in AARP on this subject. Some helpful hints they gave were:
1: Go to the source. Call the venue directly or visit an event's official website.
2: Join the club. This can be fan clubs or venue memberships etc..
3:Act slowly when dealing with brokers. Remember the closer to an event the more likely prices will drop. They don't want to get stuck with tickets.
4: Hit redial. No show is sold out until the curtain rises. Extra shows may be added. Sponsers may not use their full allocation of tickets. Ticketmaster often puts tickets back up for sale if a buyer's credit card is fraudulent or no good. Call the box office the day of the performance.
5: Make a bid if price is no object. Look for "authorized" auctions such as those operated by Ticketmaster. Many artist set aside seats to keep them away from scalpers.
6:Beware of e-tickets that you print from your computer. They are legit, but bewary of secondary sellers. There is nothing to stop a scalper from selling copies. If you buy from a reseller ask for a hard ticket.
7: Research their rep. It's no guarantee you'll get a good deal, but make sure the broker is lcensed by the National Association of Ticket Brokers (
www.natb.org). Buying from a real storefront can help too, since you can see the tickets. And check the seat map: those great seats on sale might actually be nosebleeds.