J Rock Concerts Tokyo area

I am a new to Japan and I would love to go to some J-rock concerts. Unfortunately i dont really know people who live in or near Tokyo, which are interested in it :/

How is it, if I would go to this alone? I am european female.
Anyone has experience?

And where could I find people for concert meetups in Tokyo? Are there any good sites etc?

Thank you

In my last time in Japan I went to Rock in Japan festival-last august-, in mito (about 1.5 hour by train + city bus). Bump of chicken, asian kungfu gen., baseball bear, etc.
But most of festival like that are on summer time. Now if you look for an individual band, you should look at every band website you are interested in, and see when and where they are playing (most bands makes national tours every year, mostly between may and november)
I hope that was useful to you.

I went to a lot of concert alone and since you're only there from shortly before doors open I never felt awkward being on my own.

You can check visunavi.com for lives.
Actually there are concerts like everyday.

Additionally most lives are visited by at least a few gaijins and you'll probably automatically going to talk to those.
If you are more of a shy type just go an ask what ticket number they got - seems that this is one of the most common ice breakers : )

Here is a website I use for JRock concerts and it also indicates concerts from other parts of the world as well. Have fun! I go to Buck Tick concerts by myself every time they put out a cd and I'm flying from Canada just for those concerts! You are not alone! Check out:
http://www.jame-world.com/us/