Really you should have the same OUTCOME from both charts. The difference should only be in methodology. Unless (a) one system is fundamentally better than the other or (b) the reader you approached for one was either significantly better or luckier than the other.
I'd like to point out that there is waaaay to much automated BS on the web these days passing as astrology. It's slightly better than the "starscrolls" and "dear abby" type astrology popular in the pre-www era but it is still NOT a real reading. A real reading is when an actual PERSON sits down and personally goes through your horoscope with you. 90% of the people who think they have had a "reading" - eastern or western, have really just gotten a computer printout. With which they are left to their own amateur proficiency to understand and interpret.
Adding to the mess, from those printouts people ask isolated questions to free message forums where they get quick and usually un-educated answers which they expect to be accurate and deep.
It's a mess, really.
People who really care more than a slight curiosity about astrology really need to find a personal astrologer, just as much as people who care about their health should have a regular doctor.
~~~~~~~~~~~~~~~~~~~~~~~ FOLLOW UPS ~~~~~~~~~~
~~~"I have visited several computer generated sites and I have seen slight differences in them.....I was so curious about it that I actually bought a couple of books so that I might try to sit and work up my own chart - then compare again."
Really you cannot learn astrology from books, although books do have an important role to play. Astrology is a divine science. It must be passed from the heart of one living being to another. Books can supplement this. If you want to learn enough astrology to be your own astrologer you should have an astrology guru or teacher to give you the divine understanding of this sacred science.
~~~"In regards to Vedic vs. Western astrology - isn't Vedic astrology more up to date in your opinion?"
a) It's my opinion that truth can be obtained through either methodology and though many others.
b) It's a hard fact that the Vedic zodiac is astronomically accurate and the western one simply is not. Rembember what I said in "a" above, too.
c) Because the Vedic zodiac is astronomically accurate, fundamental and basic methods of interpretation and calculation still yeild significantly accurate results. Whereas in the western system accuracy is still quite possible, but needs to rely on comparably confusing and advanced calculations and methodologies.