Hmm... I work at an academic library, and am hopefully soon to create a searchable online bibliography for them. (Whoever is reviewing that grant, please approve it.) Perhaps I ought to ask my boss about that ;)
Brett, you need to add an underline to the codes...I had to use <url>.
No, no, for propper structural mark-up he should add [title_of_a_book] and [name_of_a_ship] ;)
Well... choose your favorite style guide. I've seen two different approaches recommended: enclosing website titles in quotes, and italicizing/underlining them (generally the style is that these have the same uses: italicize when possible, but substitute underlining in handwriting or typewriting -- so Brett doesn't really need an underline code; we can use italics).
Under theModern Language Association [mla.org] format you'd treat a website sort of the way you would a magazine: italicize the site title and enclose the titles of articles within the site in quotes.
Electronic addresses like urls, according to some style guides, should always be enclosed in angled brackets, but others say instead to use italics to differentiate them from the rest of your text.
Of course if you're writing in html most of this doesn't apply. :)