regarding articles, you can google "soa" and you get as much as you want, but for starter you might want to consider http://www.sun.com/products/soa/index.jsp or http://www.service-architecture.com/

for project  idea, I have two hints

1) choose  an industry and then try to come up with a composite solution for integrating services with two of existing ent apps within that industry, such as e-commerce, telecomm, anything, in simple terms try to merge two ent solutions so they can inter-communicate.

2) pick an enterprise applications  that require variety of platforms, hardware and interfaces (web, command line, thick client) to function (a multi platform  solution) and propose a soa  based solution for integrating them, but note that the solution should provide bidirectional communication among ent apps through services that you are proposing.

keep it simple for your project to wrap it up easily