Nearly all of my best experiences at this hobby of ours stems from the months I have spent in Mexico. It is an amazing place. But it does require quick and on the spot thinking.  Your right of course...Walking the streets at night is a very bad idea.  IMHO Verified providers are hard to come by - as they only work at this for a short while, saving money to return home or open a business of some kind.

Here's what I do.

1. Go to the bars where the party scene is happening. An upscale place where "Strippers" are on hand - is perfect.
2. Spend some money tipping your bartender or host. Get friendly.
3. The hosts will shoot Ladies your way, and they will approach you and ask if you want company. Then take a seat, order a drink, and warm up to you. Pretty quick too.
4. Each bartender, host and lady is different. Each situation is different. You be the judge. But ALL of them know a TS nearby. All of them like money. You need the info they have.  
5. Keep at it until you have several options. The name of a club nearby where a TS works the floor dancing. A TS friend they know. The host may even make a cell phone call and send for one. Cash is king here.  
6. Once you have found your lady establish trust and enjoy of course - but for me? The best part comes next...
7. Get her phone number, ask her out on her next day off. She may require bringing a girlfriend to feel safe and thats ok.  
8. Follow up on the date and spoil the hell out of her, which will be surprising easy to do. She will soon relax and ditch her girlfriend.

I have done all of these things and had many warm pleasant nights in the company of beautiful TS ladies all over Mexico. My foundest memories are of driving a convertible at sunset, with a Redheaded beauty beside me, watching her smile and sing along to the music of "The Gypsy Kings". She told me later she always felt like a princess being wih me.... and I have to say I felt like a King.

Be safe, be smart, be generous and happy hunting.