Well, for starters, i started an altmer destruction/ alteration mage and i want him to marry the only possible high elf in the game, that radiant raiment gal. The problem is i did her quest and now i am to invest in her store yet i am not given the option. So i draw the conclusion that i have to raise my speech skill, but I have no idea how to raise it other than paying gold to be trained or just passing speech checks with npc's which is hard at such a low level. Help would be great mates, cheers

Buy and sell stuff. That seems to raise my speech skill. Lots and LOTS of stuff.

When a bandit says "hold it, you need to pay a toll to pass", instead of killing them, negotiate. Every time you pass that way you can increase your speech skill. And like tobs says, buy and sell stuff. Lot's of stuff. You need to look at the perk tree for speech, because somewhere up that tree there is a perk which gives you the option to invest with a merchant. Until you meet the requirements for that perk, you won't be able to invest with a merchant. Your chosen bride may require a longer "courtship" than most of the marriage options in Skyrim.

Too bad that Bosmer at the Black-Briar Meadery doesn't give those free Speech levels up before.