The one mnemonic strategy that has been investigated quite extensively by researchers is the keyword mnemonic. This has been used successfully in a variety of learning areas, but its chief use has been in the area of learning vocabulary.
The keyword mnemonic is certainly an effective technique, particularly for learning to read in another language, as opposed to writing or talking (where you have to actively remember the words you want, rather than simply recognize them when you see them). But I wouldn't advocate using the keyword mnemonic on 1000 words, or even most of them. I would keep it for the hard words. (Read more on the usefulness of the keyword mnemonic for learning vocabulary. Find out what the keyword method is here)
This is essentially the keyword technique, but simplified by fact that someone else has done all the hard work. Dr Michael Gruneberg, a British academic who has done a lot of work in the area of practical mnemonics (a rare concern among academic researchers) formalized the Linkword technique for learning foreign languages, and has produced Linkword books for learning French, German, Spanish, and Italian.
The books aim to quickly teach you a few hundred words of your chosen language (my own count of words taught in the German book was 355), by giving you a linking image to use. Thus, for Raupe (German for caterpillar), you are told to imagine a caterpillar with a rope attached to its middle.
As you would expect (Dr Gruneberg does know his stuff), the books are designed with an eye to fundamental memory principles. Words are grouped according to category; only ten words are given at a time; words are reviewed, etc. Simple grammar points are also included. It's well organized, and I do think it's an excellent way for a beginner to get a quick introduction to the language.
Apart from my general criticisms and warnings about the keyword technique (for which, see my article), my principal caveat is the difficulty in forming the visual images. For example, for Hummer (German for lobster), we are told to imagine a lobster with a sense of humor. Similarly, for Motte (German for moth), we are told to imagine that our personal motto is "I like moths". Personally, I don't find it particularly easy to visualize these "images". Now, I mean no criticism of Dr Gruneberg, the difficulty is experienced by anyone trying to find images to express verbal connections; some words just don't lend themselves to being images. But of course, verbal mnemonics are just as memorable as visual mnemonics, and infinitely more flexible. I assume, although he doesn't say it, that Dr Gruneberg means by "image" something more movie-like, with a sound track.
There are also Linkword courses available, in a wider variety of languages, and for some languages, at more advanced levels (this link is for a British site; here's a U.S. site).
Linkword books available from Amazon
The various list-learning mnemonics - the method of loci, the pegword method, the link method, the story method - can all be adapted to help you learn lists of words. In general, learning lists is not a particularly useful technique for learning a language, however, there are some circumstances in which it can be helpful.
If you do need to remember a list, my own recommendation is the story mnemonic, unless you are already expert at one of the other techniques. The advantage of the story mnemonic is that it is very simple to master.
Here's an example of its use. I'm brushing up my Latin, and like to run through the various conjugations and declensions in my head before going to sleep (it's wonderfully soothing!). To ensure I cover them all, I've devised the following mnemonics:
I love to advise those who rule that sums are fooey. [1st conjugation: amo, I love; 2nd conjugation: moneo, I advise; 3rd conjugation: rego, I rule; irregular verb to be: sum, I am; fui, I have been]
At the table the daughter awaits the master; the son awaits the god in the field where the boys go to war. The king tells the legion his name is a burden. The citizen lies on his couch in the city. [1st to 3rd declensions, with variants]