Background and Identification
The HP LaserJet 1012 was introduced in 2003, and was one of HP's first low cost LaserJet printers. The target market for this printer was typically home users and small businesses with light printing needs when it was new.
This printer uses the HP 12A toner cartridge. HP rates the 12A to get ~2,000 pages (5% coverage). This toner is not chipped, so the levels need to be monitored by visually looking at the print quality. If your toner appears to be fading and shaking it does not work, the toner needs to be replaced. However, this also means that you can print with one toner as long as you can without worrying about the printer tracking your page count.
Genuine (Not cost effective)
3rd party (Re-manufactured/Compatible)
The age of this printer (and the lack of a chip) means 3rd party options are plentiful. In some cases, you will find 3rd party toner is more common. In many cases, aftermarket toner is often more cost effective then the genuine HP cartridge for printers like this.
Since HP has never lowered the price of OEM toner, these toners are hard to justify.