Rune HQ might not be good for prices on items, but I do believe it has great database on where to get these items. The items database has mostly all the pictures for everything in their database. The databases have mostly all the stats for everything on their list, also which monster drops these items. They're not that good for exact prices but if you really want to know the exact price, you should just go to the grand exchange or trade with someone.
Sal's Realm of Runescape Has great training guides for your non-combat skills and has great miscelaneous guides. They're quest helps are good to but I still prefer RuneHQ for quest help.