There are options to Post directly using mail or atom process but i haven't tried that so far and a bit security risk is there. You can try that option
Just start writing with word and then copy-paste it. There is no automated way to make content for blogs
If you use wordpress or blogger or any of the others they will allow you to create your own blog posts fast, depends how quick you can type. I do infact realise what you are suggesting, but you said your own posts, so for them to be your own, you need to have typed them, or used a device of some sort if you were disabled for example. Anything beyond that or paying a writer means you are rewriting others peoples, which is pointless.