Readily available from many companies, under many brand names. Some of the more notable ones are BP Microsystems, Data I/O, Needham Electronics, Xeltek, and EETools.
There are, essentially, two classes of device programmer: Fixed- family (my term -- there may be a more correct one) and 'Universal' or 'pin driver' types. The fixed-family systems are the least expensive and simplest in design. The pin driver systems are much more complex and expensive, but they have the potential to be able to program just about any chip that can be programmed.
You are limited only by the features you want and, as a direct result, how much you choose to spend. Basic memory-and-microcontroller- only programmers can often be had for less than $100.
Universal or pin-driver units, the ones that can handle a much wider range of device types (including bipolar PROMs, PLDs, etc), start around $250 and go sharply up from there, clear up into the five-figure region for the top-line units like the Data I/O System 3900XPi.
Searching Ebay for the phrase 'Device Programmer' or 'EPROM programmer' will often get useful hits.
Alternatively, if you decide (after digging around) that a device programmer is too much of an investment for your needs, there are companies (SHAMELESS PLUG ALERT!), such as mine, that provide programming and copying services for a small fee. If this sounds more to your liking, check out: