I'm not particularly religious, but I looked up some Bible verses to see what it says. There are numerous negative passages on the subject of sorcery and mediumship. Deuteronomy 18:10 sums it up pretty succinctly.
"Let no one be found among you who sacrifices his son or daughter in [a] the fire, who practices divination or sorcery, interprets omens, engages in witchcraft, 11 or casts spells, or who is a medium or spiritist or who consults the dead."
Of course, that is not what magicians do. At least I've never heard of a Christian magician actually calling on demons or sacrificing their children. That scripture refers to people actually trying to practice real magic with evil purposes. You are right that the bible is open for interpretation. However, that is not to say that we can't figure out the meanings of most of the scriptures. That is why there are so many translations.
A lot of the bible is very easy to understand. However, with many scriptures it helps to read several translations and understand the geo-political landscape of the times in which it was written. Sometimes, after you get a more complete picture the meaning is completely different than a modern-day, English reading of the text.
From the FCM web site
When the Bible uses the term "magic" (e.g. Exodus 22:14) or "sorcery" (Deuteronomy 18:11 et al.) or "ventriloquism" (e.g. Isaiah 8:19), it is clearly dealing with man's involvement in the supernatural, often with the collaboration of evil spirits. The context of the Bible prohibitions make it clear that God does not want man to dabble in games with the devil. Today's manifestations of these forbidden activities are such things as ouija boards, tarot cards, the occult and horoscopes. The Christian has no business playing with these, since they open the door to demonic influence.
A problem rises from the fact that certain words have two meanings. "Magic" has the meaning of witchcraft or sorcery, but the word also means sleight of hand and illusion, the surprising and fascinating modern entertainment medium. Obviously the Bible is talking about the first of these meanings and not the second