Oh, wow, there are a lot of responses, thank you. I'm a little slower getting back to this than I would like-
INTJMom- I will ask one of my friends to help me as soon as I get the chance. I'm not overly critical with myself. I like to do things reasonably well, but I tend to disregard schoolwork or activities that I find tedious or unproductive, often turning in work that's good enough to get me a grade, but not a bit beyond. I get very indepth once I find something that interests me. I generally like my best efforts. Musically is the one area where I'm never content with myself.
From the childhood quiz, I scored as an ENP. I
was more outgoing a few years ago. The details sounded right as well.
Randomnity- That was an interesting profile, and different from most of the stuff I've heard in relation to ISTPs. Some of it seemed very much like me, such as their "Contributions to the Organization" section in the summary, and the enjoyment of completing something tactile, but the rest of it doesn't quite seem to gel. I'm really not much for sports, extreme activities, or living on the edge at all. I also don't require doing something to learn it, I'm content to stick with the theory at times. This really does make me consider a Sensing type, though.
athenian200- Thank you, but I think I have to attribute my lack of spelling mistakes to Firefox's built in spell check.

The comment about my lack of organization due to a low S confuses me a bit though, as I usually am quite close between N/S.
"?"- Finding out my temperament via my interaction style... I assume you mean just watching how I react in situations, are there any specific things I should think about in relation to any specific type?
ptgatsby- Ooh, that's an interesting concept, one that I'm comfortable with. So, is there still a point in determining type now? Which is the approach taken with this- consider yourself an 'n' but be aware of the possibility of future change? I'm not sure.
As to the left-brain, right-brain, word choice and clarity discussion, I really don't feel like I know enough about the whole concept to really weigh in... hence the thread! I strongly believe that you have to be able to get ideas across when necessary... grammar seems to be a decent start towards this.
"?"'s writing qualities of an INTP does sound like me. The INTJ sounds far from it, if they are usual attributes.
A question- how much does David Kiersey's ideas differ from the MBTI? I don't know. I was just lent his book regarding temperaments, but I'd like to know how much of their concepts are interchangeable, if any.