Right to Appeal Conviction and Sentence advice. In December…

Right to Appeal Conviction and Sentence advice.
In December 2007 I was arrested for possession of a Schedule 2 dangerous drug and supply of a dangerous drug. In October 2009 we were going to trial. At a pre trial hearing it was ruled that my evidence for my defense was inadmissable because it was hearsay. (text messages, possible police report of a seperate incident of the co-accussed). Due to the fact that I had no evidence to produce at trial my barrister suggested that I change my verdict to guilty and made a deal with the prosecution that I serve no time in gaol and 12 months parole. I reluctantly accepted this offer as I was under pressure due to the circumstances and my barrister, mother and partner thought it was the best deal to end my court proceedings that were taking it's toll on my health. The judge did not accept the prosecutions deal and gave me a 15 month gaol term with 3 months to serve and 12 months parole. I served my time in which I received a letter from the solicitor that was present on the day of the pre trial (first time that I had met him), stating that I should not appeal as the sentence may be increased. I did not appeal and served my time and did my parole without incident.
I have recently been told that my conviction & sentence were harsh and that I did not receive fair treatment or representation and that I should have gone to trial or appealed. What are my options now to have my case retrialed or my conviction overturned? I maintain my innocence.
Some of the things that I would like to mention for appeal is that my barrister did not represent me properly, I tried to change barristers about 6 months into my court proceedings but there were complications, at a basher enquiry at the pre trial hearing the police supeonaed the person accussed of setting me up to give testimony against me when she had already admitted to police as being the drug courier for the co-accussed which they mistook me for, my text messages for my defence were inadmissable as evidence when I was convicted of supply (which was the gaolable offence) based on a text message from my phone which I did not send that was a question only, the text message from my phone was never discussed at any time in the trial proceedings as being sent from me and the police were informed by myself when questioned at the time of the arrest that I did not send the text message, the barrister never questioned the validity of the text message on my behalf or that I never sent it, I had never been in trouble with the law before (not even a speeding fine), the barrister did not question the sentence imposed, the barrister never mentioned that I cooperated with the police at all times and even admitted to police my experimentations with drugs and the presence of instruments used for drugs at my place of residence before a search was conducted, the fact that I was arrested unlawfully in the first place (the police raid was at somebody else's place and they arrested me after I was asked to go to the station and I told them I knew nothing of this person or about any drugs in that house and that I could not help them with their enquiries. When questioned why I was then arrested they said that my mobile phone was found in the same vicinity as the bud of marijuanna that was found at this person's house), the fact that my bag was searched at the other persons house twice and nothing was found and then at the police station when logging in my handbag - which I asked to take with me to the police station - drugs were suddenly discovered which in turn incited the emergence search of my place of residence, they denied me a phone call to my work which in turn lead to my dismissal, they didnt provide me with the yellow pages to seek legal representation when I told police I didnt know of a lawyer, the police were obviously set out to get me as they fought to deny my bail, they kept me in lock up overnight and it was only due to a desk clerk at the watchhouse asking me a question that I was seen by the duty lawyer and put before the court the day after my arrest at 4:30pm on a Friday, the barrister never mentioned that I had become mentally ill due to the arrest, barrister did not fight for any other deal with the prosecution, the fact that I was severely depressed & medicated at the time of my decision making at court, police lied about why I was locked up overnight, police produced incorrect falsified evidence. That's most of it.
I am on different medication now and not zonked out all the time. What can I do? What options do I have and where can I go to seek additional help or to start an appeal? What will I need to do? And what regulations, acts or other legal documents can you refer me to so I can gather more information? My carer and I will have to do the majority of the research as I'm on a disablity pension (due to conviction & sentence) so I'm unable to afford private legal representation. Please help with as much detail as possible.