I met DH on Match married at 35, had DD at 36.
I had two DS's from previous marriage.
I decided to get serious about dating and treat it as a business. I read all the dating with Match links, some of them American and read some really good articles on getting serious about dating.
These were the key things I remember:
Be really honest with yourself about what you're after. If you want a long term relationship and DC don't be scared of that. If you meet someone who says they're not sure what they're after move on.
Try to have three people you're talking too until you know you're mutually serious about one person. Don't chat for weeks. Have a few online exchanges and they're either up for a brief meet or not in the right place at this time. Be bold and ask them if you're interested. If you're not, be polite but move on. If someone is nice but not for you then dont string them along, its unlikely to change. I'm not a believer in theres only one person we can love but there's lots of people we know we really aren't likely to want to spend our lives with either.
The reason for three. Two you play off, one and you deflate if they are not in the right place, three is not so many you're really busy (you meet each max twice then decide)
Keep meet no.1 somewhere public and brief i.e. coffee in the daytime in town. Have a meet no.2 option ready.
Get a seperate payg mobile phone for contacts and use first names only. You don't need to give details of your address of living arrangements initially. That can happen over time.
There are lots of other people also looking for serious relationships out there. Online is a great way for you and them to sift through.
The mumsnet dating thread helped me through. Lots in the same boat and always good to have people to laugh with.