OK, tried my serch-fu and failed, so here goes:

With the spirits /tradition connection, are those the only spirits they can summon/bind, or are all spirits availible? For example: A Christian Thuerge wants t summon a Task spirit, can he? Do those spirit listings mean anything other than color?

A mage can only summon the five spirits of his Tradition.

OK. Is there a location in the books where it says that - in case my player gets upitty.

The most clear:

SR4A page 188:

"A magician may only summon the chosen spirits of her tradition (see Traditions p. 180)."

Cool, thanks.

Now any mage can Banish a spirit to reduce its favors, then use Summoning on the spirit before it departs to bring it under the conjuror's control, as per SR4, page 180, Banishing, 2nd paragraph, 3rd sentence.

Also if I remember correctly there is a metamagic that allows you to get a spirit outside of your tradition in Street Magic or I may be confusing that with a similar echo from Unwired.

Just the Echo for sprites; there is no analogue for spirits =/

Really? You think there would be. Huh, well I think I have something to run past my GM then.

Yep, I have it house-ruled in my campaigns, but it's sadly not RAW =/