Thankfully, I think I found the problem. It seems that the earlier in the day I practice, the brighter I am and more likely to find problems instead of exacerbating them.
Hunter;
I am absolutely brand new to the guitar. I tried playing when I was younger but at that point my hands were too small to wrap around the neck of the guitar. I have extraordinarily small hands, palms and fingers alike. I've only met one adult with smaller hands than mine, so you can imagine in adolescence that this might have been an issue with a full sized guitar, since my hands hadn't grown into themselves yet. I used to play piano (self taught) with some success and have repeatedly struggled with the flute, which I want to be able to play but just don't have the mental energy for. My first teacher was so horrid to me (and not a good teacher either) that I find the instrument discouraging, particularly since my flute came to me needing to be re-keyed (that one was fun!).
Due to other activities that I've done, I'm accustomed to the need to achieve muscle memory and dexterity in other activities. I think that my initial concern was that nobody else seemed to be struggling with this so is it something wrong with me?
Razbo;
I cut my nails down as far as they'll go. The nail bed still extends beyond the tip of my index finger, which is part of why I think I'm having a problem. I feel forced to use the tip of my fingernail to hold down the string and that's not an effective way of doing what I'm trying to do (needless to say, I'm sure).
Do you have a link to the exercises to which you refer? I'm not sure where to find them.
maltmm;
You're right; a few minutes ago when I sat down more relaxed I discovered that the main problem appears to be that the angle of my hand was wrong. I'd realized this last night but upon experimentation I think I'm on track to get it into the position that I want. Angle is half of the problem, but it's a heavy contributor to the other problem; I'm not holding the strings down hard enough, so I'm not getting the proper tone. Now that I've got it figured out I think I can move forward without too much more disappointment!
Carl;
The guitar was checked over less than a week ago and everything was in order, so I don't think that it's the guitar itself. It seems that the angle of my thumb and wrist were awkward. My hands are recovering from years of knitting, which requires a different position but similar learning pattern (in terms of learning new muscle use, etc).
Thanks everybody! I'll let you know how it goes!