last year at newcastle i went to the venue at 11.00am (i work 10 minutes away), and took an A4 sized "The world is Ours" promo photo which i printed off the internet on glossy paper, and as soon as i got there phil was just getting off the bus to go in, he signed my photo "to simon, best wishes, phil campbell".
2 minutes later mikkey come out and added his autograph. only lemmy left then!
i hung around the tour bus and sure enough, about 20 minutes later the door opened and there stood lemmy. he signed my photo and even let me get a quick photo with him (thanks to Alan Hungerford for this-a diamond geezer who will be missed!). just to point out though, that lemmy didnt go in the stage door as phil and mikkey did, he went in the door directly opposite the tour bus, which was at the other end of the city hall, he took the shortest route from the bus into the venue.
so, within about 30 minutes of getting there, it was that quick, i had my photo fully signed and a photo with lemmy. i couldnt believe my luck, and my signed photo is now framed and hung on the wall...my pride possession.

get there early and hang around, mikkey and phil were in and out during the afternoon, but i think that once lemmy is in, hes in till after the show.

good luck.