Professor Messor - check his youtube channel, also has a website, also does a monthly A+ 2hour live session (Q&A) Get your hands on his A+ notes they're great and once you can safely say you know them notes in depth you will pass the A+
mike meyers - good books i used his books + videos along with messor
measureup and certblaster are good but cost money.
i passed the 220-801 , for some its a easy exam for some its not (depends on experience around PCs.) for me the A+ was harder than the Network+ as there was more of a variety of topics to learn , where as network+ is just network based.
for more info this is a good site for all your needs
http://www.techexams.net/forums/a/
my advice for taking the exam or at least the study method would be to have a timeframe in mind. Doing a hour tonight then not doing another hour for a week wont get u there. You will have to imo dedicate several hours per week constantly to learning and retaining the info.
i still have several things i for the A+ that will be still relevant to the 900 series so if u want them send me your email i will forward on what i have.
p.s go to comptia and download and print off the objectives for a checklist
p.p.s do you mind me asking why you want these certs , are you looking for a career in the IT industry?