I tried various different free apps, some of which were not too bad. However, I got to the point where I really needed something a bit more structured so I took the plunge and bought the full iWorks suite - Pages (Word), Numbers (Excel) and Keynote (Powerpoint). They cost £6.99 for each one and I have to say I was really impressed with the functionality of each. OK so they're not full Microsoft applications but for they fulfill all my needs for my office stuff. Pages is partucularly easy to use I find, especially when creating/formatting documents with images incorporated. Word always confuses me with the positioning of the text etc but in Pages you just drag the picture around and the text auto wraps accordingly.
Once done, simply save to iPad (auto backup to cloud) and share via email, iWork, iDisk whatever. You can wireless print as well but it does need a device that supports air print.