[Koha] Ahoy!

[m freiert]

hi all.

a friend pointed me at the koha software and i've a few questions about 
it that i'm hoping someone can answer.

in short, i'm a moderately skilled geek with zero *nix skills, but 
strong information architecture, and a high general computer proficency, 
and decent windose skills.  i'm looking at doing some reasonably serious 
digging into linux in the next ~3 months.  i'm one of two people 
recently placed in charge of a small privage research library that's had 
negligible maintance for ~20 years.  i have quite good library research 
side skills, but neither of us have been on the admin side of one 
before.   we have a varied selection of books, a number of which we wish 
to allow limited access to, for several reasons.

slowly but surely our collection is being entered into an old version of 
file maker pro (because that's what our data processing volunter is 
familiar with on a moderate level) and being cross referenced with our 
old paper card catalogue and confirmed as books on hand.  now while this 
is far from ideal it *does* get our catalogue into ... well, into the 
20th century at least.

long term, our goal is to get not only our catalogue online but to share 
it amongst several other private libraries, and ideally integrate it 
with a number of university and other research and rare books libraries. 

(as a side note, eventually another goal is to get a significant ammount 
of our rare books online in an e-book/pdf format for both public and 
research access, but that's a whole nother nightmare involving long 
nights with a right angle scanner, and getting ocr software to play with 
1700 era german fonts)

questions:
-how much trouble am i looking at to import our extant cataloge into 
koha, multiple steps is fine, but manual is not pretty.  i can get us 
running *reasonably* well for the time being and even online with 
filemaker, but clearly migrating to a standards compliant software 
sooner rather than later is a better option.
-how hard is it going to be for my marginally computer adept, but 
intelligent, and data input adept volunteer who's a bit of an old dog to 
learn to input more titles?
-how hard will it be to search/compare/semi autonomously add LOC 
cataloge numbers to known volumes?  i know we have a number of privat 
printings that are probably not catalogued thus far, and will need to be 
hand numbered, but it'd be nice to not have to look up ALL of them.
-how secure is koha when on line?
-are there multiple levels of access?  i.e. can i mask certain books 
that are flagged as do not check out from being seen by remote users, or 
a specific class of users, and yet leave them accessible to local users, 
or authorized logins?

that's all i can think of for the moment.  feel free to abuse me for my 
lack of knowledge about the software, etc.

-m