I'm a real fan of lectures. Try simple lectures. You can buy this book or a simple book like this:
Developing Reading Skills Begining (version)
New edition (1994 or after that)
Read the first unit and give lectures to yourself or to the walls loudly. Follow this procedure:
1) read a few sentences, then repeat them by heart (loudly).
2) read a few more sentences, then repeat them loudly.
3) repeat the whole sentences again.
After a few month you'll see you can remember lots of words easily.
It's a very common feeling. What you should try to do is not worry about making mistakes, but concentrate on getting your message across. If you do that, then you are doing the most important thing. If you're struggling to find the words, use hand gestures to let the other person know. Remember, when you're speaking someone else's language, you are doing the hard work, so don't feel nervous or shy. ;-)