World of Warcraft®

I want to get some guild rep and I guess questing is a good way. Where should I quest to get the most rep?

The amount of guild rep you get is directly tied to the amount of XP the quest would award. This means do the highest level quests you have available to you, as well as level 85 dailies and level-scaled dailies such as the city cooking and fishing dailies.

Where are the daily quests?

Where? Everywhere. You've got the Tol Barad dailies. Quests for the Wildhammer Clan in Twilight Highlands (need to have gotten to that point in the zone's quest chain first). You have the Molten Front dailies (you need to have finished the Mt Hyjal's quests up to Aesina's Miracle). There are even a couple in Uldum, if you know where to look.

Considering that you have the achievements for each of those zones, you should be able to quest in any of those daily hubs.

You may want to skip the two Uldum dailies as there are probably more efficient ways of getting experience with a lot of other dailies. :-)

Also wearing a Guild Tabard will increase the rep that you gain with each quest or daily.