is dmt an alkaline?
and are alkalines attracted to acids?

My understanding is that yes.. Alkaloids, as the name say, are alkali-like. Due to the nitrogen, they have a slightly negative charge, and the positively charged ion (H+) from an acid would be attracted to it, so the alkaloid would be protonated and in it's salt form when there is a bond between the acid and the alkaloid.

Im no chemist and there for sure are many twists and turns to it, exceptions and so on, as maybe some expert will add or correct me, like zwiterion molecules that have two charges in different parts of the molecule
http://en.wikipedia.org/wiki/Filesilocybn.svg



And then you have oxides too, which make the whole thing a bit more complex, like DMT N-Oxide:



It seems oxides also form salts with acids but im not exactly sure how that goes, other experts might voice in here.

Yes, DMT is a base and as such it has alkaline properties, i.e. it can raise the pH when dissolved in water. All alkaloids are like that, and as endlessness said their name is derived from the alkaline properties they have.

As a base, of course it can react with (or be "attracted" to) acids- by doing so it forms the respective salts of dmt.