You know, I knew the National Archives were a wonderful source. Not long ago I bought a copy of my several times great-grandfather's army service record dating from not long after the Sharpe era. But I didn't realise that there was original medieval stuff on the web that you can download for free! For example here is Constance's Petition of 1406 asking, in essence, 'Please can I have my lands back, sir?'
Don't expect to be able to read a single word of it unless your screen is a damn sight bigger and better than mine, but at least you can see what a medieval petition looked like, and there is a summary to tell you what it's all about. Isn't it amazing that you can get something like this on your computer, on a Sunday, within minutes, free, gratis and for nothing? And for a modest fee they'd send you a printed copy through the post.