Nephew Adoption/Guardianship Any experts out there?

I'll try to sum up our situation as short as possible: Basically this is where we're at.... My brother-in-Law (BIL) had a baby with his Girlfriend (GF). The baby was born in NV, but then moved to CA where BIL & GF played house for the next 6-8 months. After a nasty break up- they went separate ways. BIL moved to Texas, GF moved back to NV to be near her Mom. 2 days ago my Mother-in-Law (MIL) Grandma to baby- told us that GF had left the baby with some neighbors for the last 4 months, and had given the neighbors temporary 6 month guardianship. The neighbors are now wanting to adopt the baby. Now that we've heard about the situation, we'd also like to adopt or have custody of baby. BIL and GF seem to like that idea more than adopting to neighbors and have given us the OK. Basically our biggest problem right now is that we currently live in another state, and aren't planning on moving down to NV until June of 07. However, we are going down for Christmas, and GF would like us to take the baby back with us to our home state, at that time. I'm not sure what legal things could hold us back. Can this be done? Or is it unrealistic? Should we try to have a home study or references done before we leave in 2 weeks?? Time is short, and I need all the help I can get. Anyone who has advice- please share. TIA!