There are dozens of ways. Some make use of a Realtor; others don't. In brief, a few are:
**Using a Realtor**
[Note: If you use a Realtor--which is fine--ask them how they'd find lease-options. If they can't come up with more than 1 or 2 of the answers below, find another Realtor.]
--Some lease-options are listed in the MLS. Not too many, but some. That's where to begin. However, that's not where to end.
--Search for homes that are listed both to rent and to sell. There may not be any comment that the property is a lease-option, and maybe it didn't even occur to the seller. But a property that a seller is willing to lease, but is also willing to sell is a perfect candidate for a lease-option.
--Search for homes that are listed for rent, but were previously listed for sale. It's likely that the owner was trying to sell the house, but wasn't able to. Now he/she is willing to rent it. That's another perfect candidate for a lease-option.
--Search for homes that are listed for sale, but were previously listed for rent. In today's market, there will be fewer of them, but it happens. Again, another great candidate for a lease-option.
--Search for homes with expired listings. The owners wanted to sell, but weren't able to. Many will consider renting the property, especially if it's vacant.
--Search for homes listed for sale that are vacant. The owners are hurting. They might appreciate the cash flow they'd receive from leasing the property.
--Search for homes listed for rent that are vacant. Again, the owners are hurting. And most owners of single family homes are "reluctant landlords." That wasn't their long-term strategy. Especially if they're bleeding, they may just want to get the property off their hands.
***Not Using a Realtor***
I'm not advising doing it yourself, but you certainly can. Any competent Realtor--and there are many--should be able to find you plenty of lease-option opportunities using the strategies above. However, here are a few other ways to do it.
--Advertise on sites like CraigsList for a lease-option. Advertise under both the rental and purchase areas.
--Go through the papers and look for properties that owners are trying to rent out. A lot of them won't be listed in the MLS. Approach them and explain that you'd like to rent their property for awhile, then have the option to purchase it.
--Look for FSBOs. Same basic pitch to them. You'd like to buy their house, but would like to rent it first.
--Choose a neighborhood you like. Knock on doors. Ask, "Do you know anyone in this neighborhood who might be interested in selling their home?" Often, you'll turn up people before the home is listed. Again, you explain you're interested in buying, just renting awhile first.
--Put cards up in your local supermarket.
And the list goes on and on and on.
However, Texas does have some stringent limitations on lease-options. Make sure you check with a lawyer to make sure that what you're doing complies with Texas law.
Hope that helps.