Although you will have visitors who hate them, I believe a pop-up box is an excellent way to promote a newsletter. In fact, I use a pop-up box on several of my Web sites and have noticed a nice increase in subscriptions as a result. I found a script at The JavaScript Source , which is customizable. For a small pop-up window, consider using only one color versus three. First of all, I highly recommend spending some time creating a logo for your site.
Logos also look more professional than HTML text.
Your logo should go on every page of your Web site. At first glance, I thought your site was a framed site, but upon viewing your HTML code, I saw it was actually coded in a table format, which is good. However, your tables fragment your site. It appears cluttered and unrelated. Perhaps eliminating the table borders would help.