Looking for help requesting documents relating to a piece of software

I’m looking to create a FOIA request for a piece of software called TrueCrypt.

I want to see if there was any interaction with TrueCrypt or the people who ran the project that created and maintained it. TrueCrypt suddenly went dark some time ago and there was some speculation that this was in response to a national security request by the federal government either for a backdoor in the software to allow federal agents to decrypt data that had been encrypted with TrueCrypt or for some way to circumvent the encryption.

It was mainly speculation but I’m still interested in asking.

I’m a bit stuck at the stage of deciding who to send the requests to. I thought the NSA and DOJ might have been good starting points but I’m not sure if I might be overlooking something.

Thanks in advance.