Slade - probably the band of the 1970's. Collectors of the work of the four Wolverhampton rockers will be aware that there is a wealth of material to gather. One of the most interesting areas is that of the 7" vinyl single. Slade were huge all over Europe from 1972-1975 and there are a vast array of different picture covers which accompanied the single releases. Many of these are now quite hard to track down, especially in mint condition. Especially desirable are those singles released in Japan, which regularly command high prices today.

Also, keep an eye out for records by "Ambrose Slade". This was Slade's name, immediately before that became "Slade". Acetates also occasionally appear from "Steve Brett & The Mavericks" (featuring Noddy), "The Vendors" and "The 'N Betweens" (Dave & Don). You will have to be rich to be able to afford these though!

Slightly more obtainable are releases by "The Dummies" and "China Dolls" which were Jim Lea side projects when Slade were failing to get airplay. Also take time to find the excellent "Whild" CD single from 1999. 
Periodically Jim releases material under assumed names (Whild, Greenfields of Tong etc), so keep an eye out for those too.

Whilst most of the 70's records sold in huge quantity in the UK, there are still some gems to look out for - "The Bangin' Man" in a rare export picture sleeve for example and more affordable oddities such as the "Okey Cokey" 7" single - rarer on black vinyl on the Speed label than the Barn pressing or the Speed picture disc. Also, bizarrely, the single sleeve version of "Ruby Red" is worth more than the normal gatefold due to it's comparative rarity.

The US stock of the early 80's revival brings various versions and promos to track down too and there have been a host of compilations too.

The discography on this site is pretty comprehensive (already over 1000 items), but is one of the most recent additions, so if you spot anything that is missing - please let me know!