How these specific verb phrases are pronounced is going to depend on the accent and dialect of the person pronouncing them.

"Want to" can be pronounced may different ways. "Wanna." "Wunna." "Wanner." "Wunner." "Wanta." The same is true of all of the phrases you're asking about.

All of these people, however, will understand you if you pronounce the words fully and clearly. And you should hopefully be able to understand their slurred, grunted responses by context.

So the answer, unfortunately, is "it depends on who you ask."

For the record, as a native speaker of mid-Atlantic American English, if talking to a teenager, I'd expect to hear something along the lines of:

"wanted to" = "wanatoo"

"wants to" = "wantsta"

"had to" = "hadda"

"needed to" = "needed ta"

"needs to" = "needsta"

where the last "a" usually represents a schwa.

"want to" = "wanna"
"wants to" = "wantsta"
"wanted to" = "wantedta" or "wannedta"

"have to" = "hafta" or "havta"
"has to" = "hasta" or "hazta"
"had to" = "hadda" or "hadta"

"need to" = "needa" or "needta"
"needs to" = "needsta" or "needsa"
"needed to" = "neededta" or "neededa"