I don't have a recipe, but if you had say a dehydrator, ketchup, and whatsit--dextrose?--that helps dry things resist clumping, you could make your own. I believe Ferran Adria carries a powder product, on his website albertyferranadria.com.
Add the powder to your own tortilla chips that you've just fried, and should work.
Alternatively, multiplex movie theatres often have several different shakers of flavourings--cheese, sour cream/onion, that sort of thing. Perhaps Costco would carry something similar.
There's a few types of salsa -- salsa fresca (aka pico de gallo, aka salsa cruda), which is "fresh salsa" and uncooked, and if made fresh, it shouldn't be too watery (unless you add to much liquid, eg, lime juice), but letting the vegetables sit after salting will start to draw out extra liquid and could become watery.
For truly thick salsa, you have to treat it like a jam, and cook it to release the pectin in the tomato. (or I guess you could use some other thickeners ... I've never tried. tomato paste, maybe?) You don't necessarily have to cook the other ingredients, too, but I personally like roasting the peppers and onions to sweeten then up and remove some of the extra liquid. (halve the peppers and seed them, lay them on a tray cut side up with the onion cut into wedges, roast 'til they're softened, then dump into a food processor and either pulse or liquify it, depending on how chunky you like it. And the skin falls off the peppers, so I leave 'em out).
You can do the same roasting with the tomatoes, and it'll be thicker from the food processor, but you won't get the same cling without letting them cook slowly in liquid to develop the pectin. If you roast the tomatoes, I like to use plum tomatoes, as they have more "meat" to the gel around the seeds, and take out the gel and seeds.
Best Answer
You will want to remove the skins. Make a small cut on the bottom of the tomato and then drop into a pot of boiling water for 30-60 seconds. When the small cut expands to a large split, remove from the pot and drop into ice water. The skins will slide right off.
You will also want to remove the seeds. You can do this by cutting the tomato and digging them out with your finger. Cook and process as usual. You can "cook the tar" out of the tomatoes until they completely break down into nothingness leaving a ketchup like substance,.
+OR+ you can cooked mixture with whole unpeeled/seeded tomatoes, THEN through a food mill or press through a fine mesh sieve. A food mill and sieve should also catch any seeds and skins.
Edited to clarify.