First, it looks like the glossary has a wrong definition. A site is counted as a referrer for every hit, so if they come from yahoo.com, for example, then tromp around to 10 pages on your site, you'll get 1 referrer from yahoo.com and 9 from your own site.
A really useful report is in the interactive reports section. It's called Top Initial Referrers by Page. This one is VERY useful to see where people are coming from on the web.
With regards to your second question, bookmarks count as No Referrers.
Grady WernerSenior Developer / Analyst
SmarterTools Inc.
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