Hello,
I have a bunch of websites, ecommerce stores running on a 1and1 business plan at $10 a month. This was fine when I opened the store but now that they get decent traffic I feel like my pages are loading slower.
I have little experience with a managed dedicated server and felt that it was technically out of my league. I like the shared hosting enviroment where I just get a folder and don't have to worry about the server.
So my question is if I want faster page loading times, what is my next hosting upgrade step?

The next logical step would be to find a hosting provider who runs fast enough and switch over. Normally hosting providers who are not oversold will run faster than oversold providers where their servers are massively overloaded. Dedicated server is an overkill and I believe you should still be within shared hosting limits.
What is your current space and bandwidth usages?

I would also simply recommend switching to a different provider that provides fasters servers or in a less oversold environment which will also slow down even an 8 core server. This should be possible and we will be able to let you know at the chances of finding a reliable shared host if you provide us with your current space and bandwidth usage per month :)

Is there a step between going from shared hosting to dedicated hosting? I guess I'm looking for a shared server that it's as "shared" as my current one, but do any hosts have low limits on the number of sites on a shared server?

The next logical step would be to find a hosting provider who runs fast enough and switch over. Normally hosting providers who are not oversold will run faster than oversold providers where their servers are massively overloaded. Dedicated server is an overkill and I believe you should still be within shared hosting limits.
What is your current space and bandwidth usages?
My current usage is very low. I'm talking 500 visitors a day only. It's just that sometimes the pages load slower than I'd like.

Well you should be set if the hosting provider is not oversold. Your current problem is because you went with an unlimited space/bandwidth hosting provider who oversells massively and crammed a lot of accounts to the server, which causes overloads and slow loading speed.

You could look into VPS providers:
http://en.wikipedia.org/wiki/Virtual_private_server

If you are in a shared hosting environment, you might want to check how many accounts is in 1 servers. Probably you should go for semi-dedicated server/VPS before you venture into dedicated server? dedicated server...you will need to have the IT knowledge to manage it and the expenses is definitely higher.

Good luck in getting out of 1and1.