Even if you run a bricks and mortar store, having a small business website is extremely important. There are many people that search for things online and then go out on the town and shop locally for what they found. I understand that you are on a budget with little time to spare, but that's why you should be considering WordPress as a software option for running your website.
WordPress is an easy to learn and modify content management system that is open source and continually being upgraded. Open source software is free and usually supported by a fanatical community of users. These users are not only making updates in the code, but they are constantly building plugins and themes which are free or very low cost, this makes the modification of WordPress extremely easy.
Adding new content to your WordPress website is a piece of cake. With the click of a link in your admin section section, you will have started creating a new post or page. I would recommend using your posts to write about new products in stock and temporary sales and I would use the pages to post about more permanent specials and coupons.
If you don't have a mailing list, WordPress can take care of that for you as well. You can offer your customers a place to subscribe to your blog's RSS feed by email through Feedburner and then every time you post, you readers will have your post delivered straight to their inbox keeping you towards the front of their mind. This isn't the best option for maintaining an email list for your customers, but it is free with WordPress and it can be pretty effective.
I hope you have figured out by now that starting your small business website with WordPress is simple and easy on your budget.