Hi Amy!
Quite a few questions there but I will do my best.
> How do I let students see their own gradebook (but not other students grades)?
Students should be able to see their own grades (but only their grades) when they click on "grades" in the navigation block. I gave it a test on my sandbox Moodle just to make sure, and it's behaving the way I thought it should. Is it not doing this for your Moodle?
> If I created a rubric on Moodle, why can I not enter a quick grade and mark the rubric?
I'm not sure, unless you don't have permission to grade in that class. Off the top of my head, I thought Managers had the power to grade, but perhaps the roles have been customised on your site and only Teachers (and Non-Editing Teachers) can grade.
> Do you know of other places that can teach HTML, CSS and/or Bootstrap?
I think I mentioned W3Schools here. I hate W3Schools but it's how most people start. I'm a big fan of Lynda.com; expensive but quality. Sitepoint.com has some good books, but has moved to a course style site and I don't like their course quality. Sometimes you can get a discount there though. O'Reilly stopped selling ebooks on their site, but they used to be my favourite as they often offered coupons. Apress.com is another ebook site, and sometimes they have specials too.
Scott