Silver, I have no experience with the Super Snap track you have, but it is suppose to be able to mate with regular tubular 0 gauge track like that by Menards or Lionel. Reviews here of the Menards track have been somewhat mixed, with loose track pins being sited as one problem. Also Menards to date makes no turnouts, so you'll need to buy used Lionel ones.
Super Snap track was also remade by RMT, but is currently not being made by anyone. Lionel has also dropped tubular 027 and 0 from production. But the tubular 0 and 027 is pretty plentiful on the secondary market.
Really the most cost effect track is 027, but with some of the passenger cars like the 15-inch ones, you'll need a larger diameter than the standard 27 inch. 027 track was made in larger radius curves, but those are not quite as common. MARX years ago made 027 track in a 34-inch diameter.
Also consider, if you like the realism of the Super Snap track, that you can make and add additional ties to the tubular track. I've made my ties for 027 track out of brown foam, which helps to reduce the rumble noise of the trains on a solid wood surface.
Concerning your transformer: I run many of the K-Line Alco's like what you have. These have DC can motors mounted inside the trucks of the engine. The K-Line S-2, MP-15, and RDC Budd cars were the same configuration. These affordable engines tend to have jack rabbit starts with a transformer like the ZW that puts a minimal 6 volt start to the track. Really, any modern transformer that starts with a lower minimal to the track than 6 volts, would be good for your K-Line Santa Fe Alco.
The MTH locos use larger vertically mounted DC motors, so they are not as sensitive to the low track voltage as the above mentioned K-Line engines. But bear in mind the size of most MTH locos is larger and closer to scale (including most Railking locos) than the K-Line Alco's you have. So they might look out of place to you.... or they may not.
MTH did at one time make locos that came with either a horn or whistle only. These locos end with a -0 suffix at the end of the product number. At one time they re-branded some of their smaller sized Railking (number number starts with 30-) engines under the affordable Rugged Rails banner product number begins with 33-). These engines came with a horn or whistle only. All their other engines came with their Proto system. The PS-1 is the first and oldest of the MTH systems. This may need to be either replaced or removed. There are plenty here knowledgeable about MTH, so it'd be good to ask specific questions when you find a loco you think you want to buy.
I have found the Lionel 1033 transformer ideal for running these kinds of locos. The 1033 has 2 different voltage settings you can use to the track. The B-U setting of 0-11 volts is ideal for these K-Line engines. The top limit of 11 volts to the track helps to prevent these locos from running like speed demons and flying off the track. The A-U setting of 6-17 volts is good for other kinds of locos like postwar and MPC Lionel.
One more bit of info: RMT also remade the former K-Line RDC Budd Car and the S-2, which RMT made into a S-4. But RMT used a different spec motor in their locos which runs much slower than the K-Line versions, so they don't have the same jack-rabbit starts with a typical postwar transformer that starts with a minimal 6 volts to the track.
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There certainly are more choices today with buying and setting up a 3-rail layout. But with the choices, also comes a lot more confusion especially for a beginner. So continue to ask questions. Better to know beforehand, than to find out after you've spent money.
