Need help with first computer purchase


Aug 9, 2011
Hi folks,
I know this is a very basic Q for your knowledgeable community. Thanks in advance for any help.
I'm a writer/editor by trade, and after using supplied PCs for 30+ years at my jobs, I'm looking to purchase. But don't know where to start--desktop (for capabilities, ergonomics) or laptop (mobility)? Both? Which brands?
I went to a store and the guy just confused me.
Besides lots of writing and editing, and the Net, I would use the unit or units for getting into graphics, such as doing illustrations and publications layouts, and storing and working with music I compose.
Any advice/suggestions appreciated. If it is relevant I'm located in D.C. area, U.S.