A friend (girl) of mine who i really want to help is very timid to
such an extreme that friends she has is close to NIL.

What is the best approach to crack open the shell without hurting or
scaring it? I know time cannot be rush'd.

I'm the same way, and I can tell you the only way I came out of my
shell even a little is by getting a job in retail. There you are
forced to talk to customers all day, you don't have a choice. But I'm
still shy. Does she want to make more friends etc? Because I know I'm
happy with the way I am, shyness and all. I'm independent, and am
happy with the 2 good friends I DO have. Maybe she doesn't want to
change....

Your friend is very fortunate to have someone who is prepared to
invest the time and energy in helping her overcome this affliction.

I am a firm believer in alternative therapies and I read this web page
and thought it might be helpful as a starting point.
http://www.healthyplace.com/Communities/Anxiety/social_anxiety_disorder_4.asp

I'm timid most of the time...I'm only sociable with certain people
(husband, dad, brother)..the rest it kinda goes downhill from there. I
am then sociable only with people in person and not on the phone (the
list becomes a little bigger...best friends, relatives and coworkers).
The last level I would say is that I avoid conversations with anyone
else (strangers, meeting new people).

I feel stupid sometimes making conversation (I don't carry it well). I
hate talking on the phone except for the first people I mentioned.
I've never been diagnosed but I think I have a certain case of social
phobia/anxiety. The cause? I don't know really (just a natural way of
being brought up) but it's something that my husband knows about and
understands to some degree. Maybe your friend is like this and keeps
it a secret or isn't even aware she has a name for her personality.

It's VERY hard to just get into the groove of acting like an extrovert
if you aren't. The more I am pushed into a certain situation (going to
work) I feel better but it's hard to initially. It's almost like a
smoking habit, the person will only change if THEY want to.

consider the possibility of what is called avoidant personality
disorder.  There is a mailing list on Yahoo for this. Those who have
it vary widely from miserable, to actually cannot leave the house to
go to work.

http://www.tljones.co.uk/apd/apd.htm for a summary.

You might want to check out the book "The Introvert Advantage" by Marti Laney.
The author has a website at http://www.theintrovertadvantage.com/

According to stats mentioned in the book, 1 out of 4 people are introverts;
there isn't anything wrong with being one.

Depends on whether it's currently a pathology requiring psychriatric
counselling or if it's "just" general low self-esteem, shyness and
lack of experience in social situations. If it's the latter... well,
martial arts training like a judo or karate club has helped a lot of
people with all sorts of confidence issues.

If it's an actual disorder we're talking about here though... well,
then it's professional medical help she needs. Tho' if there's a
diagnosis, it's likely that the medical establishment will set up a
therapeutic regime - in which case it's possible to ask whoever's in
charge if you can be a part of any long-term desensitizing/exposure
training program. Be prepared for a no in that case though.

But as I said, if it's just shyness pushing the boundaries of what's
considered "normal", joining a karate dojo together could help lots.
Well, doesn't have to be karate, my guess is that any group activity
will help.