Hi Amtx,
At 3 years sober I'd be ready to be meeting people and dating too. I don't know about your part of the country but where I live tons of people do the online dating. I've done it and had a great time meeting nice people. I would definitely stick to that one major site and stay away from the free ones if its all new to you. There are tons of people out there who aren't into bars and drinking. They probably even have one for people who don't drink if thats what you want. Who knows? I've been dating someone for over a year and we met that way so I haven't checked it out.
The way to do it if you are interested is always meet in a public place. Coffee shops are good and go into it with just the attitude that worst case scenario is you meet a new person and maybe even a new friend. I met 3 great friends who I still stay in contact with and at that time we weren't matches but we just really liked each other as friends. They set me up with their friends too. My friend group expanded. Then I met someone I clicked with. You are young but not a kid so I'm sure you know what you are looking for and know how to do it responsibly.
Just something to consider but it may not be your thing. The other suggestions are good ones too.