Godan verbs and -tai form

I'm trying to study -tai form and got bit confused with this two godan verbs:

dictionary form -u +ITAKATTA        
iku     ikitakatta (?)    i wanted to go
kau    kaitakatta        i wanted to buy
dictionary form -u +ITAKUNAKATTA        
iku     ikitakunakatta      i didn't want to go
kau    kaitakunakatta    i didn't want to buy

Is that correct? and also i suppose i have to add -te in some cases. Is it just te-form +itai ? Like itteitai and kaiteitai ?

pardon mi english.

Correct I think.

itteitai （いく→いって　＋　いる→いたい）would be something like "I want to go and be somewhere.." It can also mean 'Ouch, it hurts' ^^

ittemitai (いって　＋　みたい）might make more sense: "I would like to go and experience..."