Another very useful site that has not been previously mentioned already is http://oakland.crimespotting.org/
I find it to be a lot more visual friendly and easy to use, you can also setup e-mail alert within .25, .5 or a 1 mile radius which would be a good idea to get a feel of the area before you decide to move into this community.
Amongst other things you can do are to speak to the neighbors, or even people that don't live there but are there often that can give you non-bias information such as the mail delivery people or local pizza delivery companies. These people will be able to tell you about how bad the crime rate is in the area more than any website or statistics can, I would also recommend driving through later in the evening to see for yourself if to see how comfortable you would be living there. Also in Oakland, there are many pockets within bad neighborhoods that I have placed buyers that still very much like the area. You should not let a bad area as a whole deter you from finding that diamond in the rough. Good luck to you!
check out the crime stats from the coom unity on this website.
That should give you a good idea.
Let me know if you need more.
As suggested already, I suggest you check the City of Oakland Crimespotting: http://gismaps.oaklandnet.com/crimewatch
Also, check in with the City Council Office there..they'll have lots of info. Larry Reid is the Council person for Council District 7. His office will have the name of neighborhood groups and key people you could speak to.
If you want to go to a neighborhood meeting and see what people are saying, check out the neighborhoods. http://www2.oaklandnet.com
I sold a house on the 2700 block of 75th Ave. last year and the buyers are very happy. They are first time buyers, have made sure their home is secure, are involved in the community there, but have had no problems.
In general, this area has had a fairly high rate of crime over the years, and it is known for this. Having said that, there are people living there who own homes, raise families, go to school, operate businesses, and this is their home. A significant amount of redevelopment funds have gone into the area in recent years, and it shows. Eastmont Mall is much improved. Check it out carefully, talk to neighbors on the block you are interested in, and do as much research as you can. Good luck.