I think everyone who joins feels this way though, it's HUGE with hundreds of threads moving around all teh time.
For me I found a home on teh special needs section, it's very small and friendly over there so was easy to get to know people and we all had something on common so again very easy to chat to each other.
The I ventured into the main area of mumsnet and afer a while things happened with certain mumsnetters and friendships slowly formed.
Like when Beetroot lost her dear friend. I really felt for her and we connected. Since then every time I see her name it's like bumoing into a good mate and we chat, we have also since had the pleaseure of meeeting and I can see who i'm talkign to now as well.
Same with Blu and Hunker and a few others. Certain conversations were struck up, they supported me when I was low and have always been there for me. Again, I've met both of them since and that just helps with our mn chats.
There are other posters and you just start 'seeing' them around a lot and you realise you like each others style and get a vibe and you get on with each other. I have loads of popel like thta on here, but it takes time. I've been here for 4 years. Just relax and enjoy it and after a while you'll get to know people and visa versa.
Mumsnet is a really kind and generous place fullof great support and advice, stick with it