As far as I know, one needs a dedicated small cap font to be able to type the letters with a computer keyboard. Otherwise one needs to use a special program such as 'Popchar' to insert the small caps where needed. This is a pretty slow process for using small caps in an epub.
If the owner of the font, such as the Fell fonts allows alteration of the font with a font program such as 'fontforge' or 'FontCreator', then one can fairly easily change the font so that the small caps are located where the lower case letters normally would be. This would work as a normal small caps font, although there might be problems with kerning if one didn't work on it.
(After posting the above material, I downloaded the Fell fonts and studied them with FontCreator. The Fell fonts may look ok on the web, and probably are usable for epubs but they are pretty crude when shown in FontCreator. I remembered then that I had done the same thing some time ago and decided they were not sufficiently well-formed for my use - perhaps this conclusion was a bit harsh, and perhaps I might try them if the small caps were accessible with the computer keyboard. I'll try emailing the author and see if he's willing for them to be altered or if he has a small cap font already done.)
Last edited by bobcdy; 06-04-2011 at 10:27 PM.
Reason: added new text