Luanda is still very much the dump that it has been for a long time....not a pleasant place, and darn expensive too (imports).
The only place I know of (and stayed at) was the Meridien, and that was also darn expensive (over $100/night). Rather ironic, considering the miserable state that most Angolans live in.
The hotel can actually be booked online at expedia.co.uk
By the by, what's all this about BA starting weekly flights down to LAD in November??
Regards
p.s. a portuguese phrase book might come in handy