RE: When "introduceyourself" is near the top, you know you are still an early adopter ;)
Welcome to steemit. In answer to your question, yes many people have various accounts for various reasons. I myself only have one account, I can not imagine handling two different accounts myself for now. Just to busy with one.
You should keep your follow me line in your post, and if you have not yet, you may want to back link your steemit account to your other accounts. The reason being is @cheetah, it is a plagiarism bot. So if you have content that you import from one of your other sites, you may get visited by them. That is really no problem at all, as it will give a small upvote, then a human will come and visit, and investigate.
I see that Newbieresteemday, and greeterguild have already been mentioned. Good groups to help new users get acquainted with steemit. There are a lot of tools to make viewing and understanding steemit a little bit easier. One of the best tools for viewing you semi hidden steemit information is https://steemworld.org/@leeharding - that would be your page. It will alert you to when people "tag" you or "shout out" your name in a post or comment.
The photography community on steemit is a very nice group of people, there are all kinds of fun share a picture contest for just about anything.
Along with the photography groups, there is a pretty good sized group of writers, independently published and small run press publishers, and some writing their books on seemit then looking to get them published.
I am sure you will enjoy your time on steemit, if you have any questions, I do not mind trying to help, or point you to some who can help if I can not.
I would not have known these things, and I very much appreciate you sharing them with me.