I know there are boosters for signal coverage and I have heard a lot
of negetive comments about how they work.  I live and work in a rural
area.  I travel with my laptop to rural areas.  Sometimes in these
earea if you move slightly you get a signal.  It makes sense that a
booster could help slightly?  Someone told me about a card I would put
on my windshield.  Also, at my home my mobile phone only comes works
in 2 areas of the house.  If there is something our there I would like
to know brand etc. and where to find it?

ruglady, 

Are you using your cell phone for both Data and Voice or do you have a
Laptop (PCMCIA) card for your laptop to provide you with Internet? 
I'll assume you have a PCMCIA card.

Who's your cell phone provider?

Who's your Laptop Internet Card (PCMCIA) provider? 

What kind of phone do you have?

How many signal bars are you getting on your cell at your home?

What's the -db (RSSI) signal you're getting on your card when it's
functioning properly and what is it when you're barely getting a
signal?

I use my Verizon cell phone for only voice.  I use a Verizon card with my laptop.
 I get one to none signal bars on my cell phone at home.  I don't know
what you mean with -db or (RSSI) signal on my laptop card.  The
VZAccess Manager shows bars just like on my cell phone.  I was went to
a remote rural area last week intending to work on the internet and
did could not connect.  I called Verizon and they said I was in a
digital area.  (My cell phone worked so I couldn't understand why my
laptop would not connect)  I did eventually find a place that the
signal would come in on my laptop, in a high place in our motor home
that was not convenient to work at. We are in Virginia.  Verizon told
me that the lower half of the state was good for broadband and the
upper half they were using other companies towers.
  In an emergency I can log on to Quick Net 2, but it is .25 a minute.

   I would not mind getting two devices, on for my phone and one for
my lap top, if need be.
   Thank you for your expertise!

If you are handy try http://wireless.gumph.org/ for laptop broadband
I Googled "home made antenna broadband laptop"

http://www.makezine.com/blog/archive/2005/08/how_to_make_an_2.html or the link @
http://robert.watkins.net/phone/
I Googled "homemade antenna cell phone"

Hope this helps!!!