Where can you find topical anesthetic and what brands are they?

Can you clarify what you need?

Do you mean a cream to be applied to the skin to numb it, or a throat spray or gargle, or what?

Like a cream to numb it

Still floundering a bit here for lack of info as to the problem but here goes:

If by "it" you mean the skin, what you want would be Emla cor Liprakaine cream (same thing, different brands, second one cheaper) which contains lidocaine and prilocaine. Can get it OTC but should read up carefully first on precautions and adverse effects as it does have some potentially serious ones. That is more likely when a large amount used and/or large surface treated. In particular be careful about applying to an areas with any sort of break in the skin.

If by "it" you mean the lips/mouth or gums, then Kamistad Gel which contains lidocaine in a preparation made for topical oral use.

If "it" is hemorhoids, then Scheriproct N which comes in both cream and suppository form and contains lidocaine and an anti-inflammatory

If "it" is your penis (i.e. to try to delay ejaculation), the creams mentioned above (Emla, Liprakaine) will work but risk of toxicity is greater. Need to apply sparingly, stay well clear of the urethra and be sure to remove all once some degree of sensation has been lost. In addition to side effects on the man, this can also lead to side effects in the woman. Really not a good idea to do this on your own, would be better done in consultation with a doctor, there are some in Thailand specializing in men's sexual problems.