For free press release submissions there are many decent sites out there where you can submit to and time taken for approval is usually a day or two. For paid distribution, prweb.com is the one I have used before.
New Press Release and Guest post site is quickinformations.com with page rank. you can use free of cost and ragister and publisht the original content to get back link to improve the ranking in search engine. now tiem google consider only press release and guest post link to improve the back link. don't publish the duplicat content on the press release and guest post site.