There are several movements of each of these but they are GORGEOUS. Definitely worth getting. They have such a heart wrenching melancholic sound to them that I can't get enough of.
One of my all time favourites is La Campanella by Franz Liszt. I am at work so I can't link it but if you are interested you can look up Valentina Lisista for her version which is my favourite of all the ones I've ever heard.
You can find a lot of the classics [of classical] on Amazon for cheap. If you're into getting digital albums, they have good ones, such as "99 etc" for instance, I have both 99 Classic Film Pieces" and "99 Cello Essentials"
Also would recommend film scores such as Dario Marianelli's "The Soloist" and "Atonement," James Horner's "A Beautiful Mind" etc.
I think my choices are nothing unusual in the sense of "it's all being said before", I like a lot but I really enjoy Schubert's Ständchen and Tchaikovsky's June: Barcarolle.