The Internet offers … “free” … online …. Bible Study Tools but choose them wisely.
Blue Letter Bible – http://www.blueletterbible.org
Bible Study Tools at Crosswalk – http://biblestudytools.com
Study Light – http://www.studylight.org
Bible Gateway – http://www.biblegateway.com
With an economy that does not look so well to some I would suggest to become frugal when you can, but use and choose “truthful Biblical applications” for studying and researching the Scriptures.
Some bookstores maybe in your local areas may even offer discounts or sales so watch out for this as well.
Build a reference library. You will need good Bible study reference resources.
Concordances, Commentaries, Bible Dictionaries, Bible handbooks, Language tools, Topical Study Tools, Maps and Charts will give you a greater understanding of the Scriptures.
Look around in your home you just might have some Family Keepsakes that are covered with dust that is worth studying from before you buy anything.