The CH341A is available in a number of configurations and maybe two variants. (Black or Green). Not really knowing what I was up to I bought a 'black' version with a complete set of add-ons for just under £10. This comprised:
CH341A 24 25 Series EEPROM Flash BIOS USB Programmer (Essential!)
1.8V adapter for iPhone or motherboard 1.8V SPI Flash Memory SOP8 DIP8 (Not needed)
SOP8 to DIP8 EZ Programmer Adapter Socket Converter Module 150mil (Not needed)
SOP8 Flash Chip IC Test Clip socket adapter BIOS/24/25/93 Programmer (Needed)
You can get just the programmer and test clip for under £5.
What turns up in the post is just the hardware. There are no instructions or software, but this isn't a problem. A quick google will find you documentation including a circuit diagram. As to software, support for the programmer is already built into flashrom
Note: One set of the documentation I found pointed out that the CH341A programmer chip is running off 5V whilst the BIOS EEPROM is a 3.3V device (and is powered at 3.3V). The implication is that the clock and data signals from the programmer may be overdriving the inputs on the EEPROM. The article goes on to show how to modify the programmer so that it runs off 3.3V as well. I, as many others have, just used the board as supplied without any problems. I haven't yet waded through the various data sheets or dug out my old oscilloscope to see exactly what is going on and whether the mod is advisable.
Also discussion on the internet implies that the version of the CH341A with the 'green' ZIF socket powers the programming chip off 3.3V rather than the 5V that the 'black' version uses. I have not seen a version to check this.