The procedure is different depending on whether you are in the "border zone", or in the rest of Mexico. The "border zone" is the area within about 20km of the land borders, and the whole of Baja California (North and South), and it is an easier process there.
Since you have a TIP (temporary import permit), you are probably not in a border zone.
Rolly Brook's excellent site on living in Mexico has some basic information on the subject.
Your car needs to be made in North America (any of the three countries), as shown by the VIN number. It needs to be a certain number of model years old - the rules for this keep changing, in 2013 it was models 6 years old or older but may be more restrictive now. There may be other cases where it's not possible, such as for some luxury cars, and some convertibles.
When I imported mine (in the border zone) a few years ago, it was only possible to import cars in the range 6-10 years old. Cost around $1000.
There's a great deal of discussion about the latest situation at Yuclandia. It does basically boil down to: find a local importer, and ask them about today's rules, as enforced by the local office. Like most things in Mexico, it does vary a lot depending on the local staff.