eh, I can perhaps offer some advise
1. yes, it's likely as difficult as they say
2. a good dictionary - Langenscheidt's are good (and I think they sell them in the US) as is the Harper-Collins. I have one of each kind.
2a. supplement that with dict.leo.org - great site.
3. audio stuff I can't really recommend, never really used such things. but I too have heard good things about Pimsleur.
4. other resources (inet) - I am certain I have some up my sleeve, just need time to dig them out. I should have time this weekend to find some good links.
5. an elaboration on point 1, i suppose ... pay special attention to
articles of nouns, and verbs - irregulars and tenses. those are the toughest points, and require old-fashioned memorisation. re: tenses - you need to understand them (when/how/why to use). It helps if you have a fair understanding of
english grammar.
reminds me, another book I've seen recommended oft is
English Grammar for Students of German
good luck!