What kind of budget are you following? A good (Dell) computer under $1000 would be Dell's Dimension E510. Here is a link to the main page for the E510 models. http://www1.us.dell.com/content/products/features.aspx/cto_entdt_e510?c=us&cs=19&l=en&s=dhs
All are good though I would reccomend the base system. It can be customized as needed at the bottom of the page.
I would reccomend HP's line of Pavilions. Dell is known for poor customer support in terms of wait time when calling for assistance. The link to the Pavilions can be found here... http://www.shopping.hp.com/webapp/shopping/compare_category.do?storeName=computer_store&category=desktops/hp_pavilion&catLevel=1
The D4100y and D4100e both seem suited to your needs.
Does anyone have advice on what computer I should buy? I've been on Dell's website and have been to stores but so confused about what I should purchase. It'll be for my home-based business used for word processing, accounting, running my website which will include posting pictures of my products and in the future some cad/cam (computer 3d design)work. Any advice is helpful. Thanks!