I would recommend a Network Extender for better coverage. The Verizon Wireless Network Extender enhances indoor cellular coverage to provide more reliable wireless service. The Network Extender is compatible with all Verizon Wireless phones and works like a miniature cell tower in your home or home office.
Here is a link for additional information on the network extender. Click here http://support.vzw.com/clc/faqs/Equipment/network_extender.html
The extender is quite pricey.... you can build several devices or use external antennas... See EVDO.com and the 3Gstore links. I use a tower and home made antenna built out of an old dishnetwork dish. You can also use aluminum foil on cardboard and set it around the device like others do to increase their cellular phone signal. Also try a usb extender cable if you have a usb device (modem).
I know the pain of dial-up! You can also rent an aircard to see if you can reach verizons towers from your location. If in reach you can check the connection strength and then figure out if you need to add an antenna and maybe an ampliflier if the signal is weak. I rented an aircard from "daypass wireless". My signal was a little weak but I was pretty happy for the 2 days I had it.
Check out http://www.mobile-broadband-reviews.com/free-aircard.html for good information on mobile broadband.
I remember seeing an interesting device to gain better siganl. It involved a USB wireless dongle, and a metal SS food strainer. He cut a hole and epoxied the USB device in the center of the expanded "dish looking" strainer. Then, using a USB extender cable, male-female, he connected to his computer. Then you can point the mini "dish" at the area that you want better reception. It worked great for him in his house when he wanted to sit out on the lawn and get connected to his wired/wireless router. All he had to do was point the mini dish at the antenna inside his house and get got a good signal to connect.
This is kind of like little bird special, cheap, cheap, cheap.. but in all honesty, it made a USB device way more receptive to the wi-fi signal.