If you're looking for custom written articles check out ccarticles.com, I've worked with them quite a few times for article writing and submission. Good quality and very good prices.
They're more SEO oriented, if you're looking for longer, very high quality articles your best bet is probably to go on a site like guru.com and find a freelance writer.
★ Sam Barrow - CEO @ SQUIDIX(1-855-SQUIDIX)
★ Ask Us About Sponsoring Your Web Site (High Traffic Sites Only)
★ Squidix - Shared, Reseller, Semi-Dedicated, Managed VPS and Managed Dedicated Hosting
★ Midwestern Web - Web Design & Development Services
If you want to republish articles from other sites,you should check ezinearticles.com and articlebase.com. If you want custom written unique articles, choose writers not article. Hire a professional write for your article needs.
ccarticles.com is a good one I hear but knowing personally beanstalk-inc.com is a very good solution, SEO services of all types short terms and long terms available, articles, copyrighting the whole nine yards.
Maybe checking them might be one of your best options.
i think writing for your own blog is not hard, just add it one by one, pieces by pieces and eventually youll surpassed that limit. cause what seach engine want its not just quality but also freshness and unique. just my thought anyway...
There are lots of articles where you can register as premium member and post your blog content in to it for some affordable prices, I suggest you to go for a article sites which has high pr and it should be of do-follow article website, where you can have more weight age than a normal article site.