I agree with Alma. You can search for live listings on Realtor.com, and it is highly suggested to find a Realtor to represent you.
Working with a Realtor provides you with an experienced agent who can conduct live searches with automatic notifications, fair market analysis, and hopefully a person who is great with conducting a full transaction including disclosing to you all known facts, conducting walk throughs, and doing the due diligence.
Trying to go straight to the source, and not having an agent representing you can lead to one sided transactions, as the Seller's agent is looking out for the Seller's interests first. I'm not saying deals can't go just great like this, but it definitely gives you an advantage to having a representative; plus, the seller often pays for any agent costs, so don't let the cost of having an agent stop you..
Check out http://www.realtor.com
I can help with any of your Las Vegas Real Estate needs or questions; feel free to contact me direct.
Mark Fleysher, MBA, Realtor